Systems and methods of remote monitoring of equipment

ABSTRACT

A corrosion monitoring device includes a sensor assembly and a detector circuit. The sensor assembly includes at least one sensor portion disposed in an interior of a pipe in a fire sprinkler system for sensing corrosion of a wall of the pipe. The detector circuit transmits an electrical signal through the at least one sensor portion, monitors an electrical characteristic of the at least one sensor portion based on the electrical signal, compares at least one of the monitored electrical characteristic and a change in the electrical characteristic of the at least one sensor portion to at least one of a predetermined value and a previously monitored electrical characteristic, determines a corrosion status indicative of at least one of a corrosion level and a rate of corrosion of the pipe wall based on the comparison, and outputs an indication of the corrosion status.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present disclosure claims the benefit of and priority to U.S.Provisional Application No. 62/620,599, titled “SENSOR ASSEMBLY FORMONITORING OF EQUIPMENT,” filed Jan. 23, 2018, U.S. ProvisionalApplication No. 62/620,590, titled “APPARATUS AND METHOD FOR REMOTEMONITORING OF EQUIPMENT,” filed Jan. 23, 2018, U.S. ProvisionalApplication No. 62/620,605, titled “SYSTEM AND METHOD FOR REMOTEMONITORING OF EQUIPMENT,” filed Jan. 23, 2018, and U.S. ProvisionalApplication No. 62/620,613, titled “APPARATUS AND METHOD FOR REMOTEMONITORING OF EQUIPMENT,” filed Jan. 23, 2018, the disclosures of whichare incorporated herein by reference in their entireties.

BACKGROUND

Corrosion is a natural process that converts refined metals to achemically stable formation. The process is a gradual destruction ofmetals by chemical/electrochemical reaction with their surroundingenvironment.

SUMMARY

Various aspects are directed to systems and methods of monitoring thelevel of the corrosion (e.g., loss of metal given in weight per area,mils, millimeters, centimeters, or some other measure of corrosion)and/or the rate of corrosion (e.g., given in mils per year “mpy” ormillimeters per year “mmy”) of equipment that is exposed to a corrosiveenvironment (also referred to as “equipment environment” herein). Themonitoring device can monitor equipment such as a pipe that can befilled with water, e.g., pipes in a fire sprinkler system. Themonitoring device can include a sensor assembly with at least onecorrosion sensor that can be used to determine at least one of a levelof corrosion and a rate of corrosion of the equipment being monitored.The corrosion monitoring can be based on at least one electricalcharacteristic and/or a change in the electrical characteristic of theat least one corrosion sensor. For example, the electricalcharacteristic being monitored can be at least one of continuity (anopen or closed circuit status) of each corrosion sensor, a resistancevalue of each corrosion sensor, a voltage value of the corrosion sensor(e.g., a voltage at a predetermined location, a voltage drop across thecorrosion sensor, or some other voltage indication), a current valuethrough the corrosion sensor, and an inductance value of the corrosionsensor. The change in the electrical characteristic can be a change inthe actual value of the monitored electrical characteristic and/or apercentage change in the value. Various electrical characteristics canbe monitored where there is a correlation to the corrosion in theequipment. The monitoring device can include a corrosion detectorcircuit configured to transmit an electrical signal through the sensorassembly and measure an electrical characteristic of the at least onecorrosion sensor that forms at least a part of the sensor assembly. Themonitored electrical characteristic can be used to determine informationthat relates to the corrosion level and/or the rate of corrosion of theequipment being monitored. For example, the monitored electricalcharacteristic and/or a change in the electrical characteristic of atleast one corrosion sensor can be compared to a predetermined valueand/or a previously monitored electrical characteristic for thatcorrosion sensor in order to determine the information that relates tothe corrosion level and/or the rate of corrosion of the equipment beingmonitored.

In some embodiments, the sensor assembly includes at least one wire loopand each wire loop includes a coupon portion as the corrosion sensorportion. The coupon portion can corrode at a rate that can be correlatedto the equipment being monitored. A geometric shape of the couponportion can include a portion having a constant diameter (uniformthickness) such as, e.g., a cylindrical shape. The corrosion monitoringcan be based on an electrical characteristic or a change in theelectrical characteristic of the coupon portion in each wire loop. Forexample, the electrical characteristic being monitored can be at leastone of a continuity (an open or closed circuit status) of the couponportion, a resistance value of the coupon portion (e.g., using at leastone of a current through and a voltage across the wire loop), a voltagevalue of the coupon portion (e.g., a voltage at a predeterminedlocation, a voltage drop across the coupon portion, or some othervoltage indication), a current value through the wire loop and thus thecoupon portion, and an inductance value of the coupon portion. Thenon-coupon portion of the wire loop may not significantly affect themeasurement of the electrical characteristic of the coupon portion. Thechange in the electrical characteristic can be a change in the actualvalue of the monitored electrical characteristic and/or a percentagechange in the value. Various characteristics can be monitored on couponportion where there is a correlation to the corrosion in the equipment.

In some embodiments, the monitoring device provides for remotemonitoring of the level and/or rate of corrosion of the equipment in asimple and cost effective manner. For example, the monitoring device caninclude a transmission circuit that transmits information related to themonitored electrical characteristic and/or change in electricalcharacteristic of the corrosion sensor, e.g., coupon portion, to anexternal device via a network for calculating the level and/or rate ofcorrosion.

In some embodiments, the monitoring device includes a corrosion ratecircuit that calculates at least one of a level of corrosion and a rateof corrosion for the equipment based on the information from thecorrosion detector circuit. The corrosion rate circuit can correlate thedetermined information that relates to the corrosion level and/or therate of corrosion of the equipment being monitored to an estimated lossof weight per area of the equipment due to corrosion to determine the atleast one of the level of corrosion and the rate of corrosion for themonitored equipment. The corrosion rate circuit can be disposed remotelyand a communication processing system is connected to the plurality ofmonitoring devices and the corrosion rate circuit via a network. Thecommunication processing system can receive the determined informationthat relates to corrosion of the one or more pieces of equipment fromeach of the plurality of monitoring devices and transmits the determinedinformation to the corrosion rate circuit. The corrosion rate circuitcan perform the calculation of the at least one of the level ofcorrosion and the rate of corrosion for the monitored piece ofequipment. The corrosion rate circuit can correlate the determinedinformation to an estimated loss of weight per area of the monitoredpiece of equipment due to corrosion, and then correlates the estimatedloss of weight per area of the monitored piece of equipment to the atleast one of the level of corrosion and the rate of corrosion for themonitored piece of equipment.

The monitoring device can include a relay circuit that selectivelyprovides at least one of a voltage to and a current through thecorrosion sensors, e.g., coupon portions, which is measured and used todetermine at least one of a corrosion level, a corrosion rate, and apresence of water. The relay circuit is operated for a predeterminedduration of time with a time period between the selective connection ofthe corrosion sensors to the power source being based on at least one ofa predetermined value and a performance criteria, which can include atleast one of a required battery life, remaining battery life, a level ofcorrosion of the equipment, and/or a rate of corrosion of the equipment.

At least one aspect relates to a method of monitoring corrosion for anequipment that includes transmitting an electrical signal through atleast one corrosion sensor and measuring an electrical characteristic ofthe corrosion sensor that can be used to determine information thatrelates to the corrosion level and/or the rate of corrosion of theequipment being monitored such as, e.g., pipes in a fire sprinklersystem. For example, the monitored electrical characteristic or a changein the electrical characteristic of at least one corrosion sensor can becompared to a predetermined value or a previously monitored electricalcharacteristic for that corrosion sensor in order to determine theinformation that relates to the corrosion level or the rate of corrosionof the equipment being monitored. The corrosion sensor can include acoupon that can corrode at a rate that can be correlated to the rate ofcorrosion of the equipment being monitored. In some embodiments, themethod of monitoring corrosion can include transmitting a currentthrough at least one corrosion sensor, e.g., coupon portion, andmeasuring an electrical characteristic of at least the corrosion sensor.For example, the electrical characteristic being monitored can be atleast one of continuity (an open or closed circuit status) of eachcorrosion sensor, a resistance value of each corrosion sensor, a voltagevalue of the corrosion sensor (e.g., a voltage at a predeterminedlocation, a voltage drop across the corrosion sensor, or some othervoltage indication), a current value through the corrosion sensor, andan inductance value of the corrosion sensor. The change in theelectrical characteristic can be a change in the actual value of themonitored electrical characteristic and/or a percentage change in thevalue. Various electrical characteristics can be monitored where thereis a correlation to the corrosion in the equipment.

The method can include transmitting information related to theelectrical characteristic of the corrosion sensor, e.g., coupon portion,for calculating at least one of a level of corrosion and a rate ofcorrosion for the equipment being monitored. In some embodiments, theinformation is transmitted to an external device via a network forcalculating the level or rate of corrosion. In some embodiments, thecalculating includes correlating the determined information that relatesto the corrosion level or the rate of corrosion of the equipment beingmonitored to an estimated loss of weight per area of the equipment todetermine the at least one of the level of corrosion and the rate ofcorrosion for the monitored equipment.

In some embodiments, the method includes periodically measuring theelectrical characteristic of the corrosion sensor, e.g., the couponportion, for a predetermined duration of time with a time period betweenmeasurements based on at least one of a predetermined value and aperformance criteria, which can include at least one of a requiredbattery life, remaining battery life, a level of corrosion of theequipment, or a rate of corrosion of the equipment.

In some embodiments, at least one client device displays the informationrelated to at least one of the calculated level of corrosion and thecalculated rate of corrosion to a user. The displayed information can bedisplayed as an indication of severity of corrosion of the monitoredpiece of equipment in at least one of a text format and a color format.For example, the indication of severity of corrosion is displayed withat least one of a first text (e.g., “NORMAL RATE”) and a first color(e.g., green) for a normal corrosion rate if the rate of corrosion forthe monitored piece of equipment is less than or equal to a firstpredetermined mills per year (mpy) value (e.g., 0 to 3 mpy), with atleast one of a second text (e.g., “INTERMEDIATE RATE”) and a secondcolor (e.g., yellow) for an intermediate corrosion rate if the rate ofcorrosion for the monitored piece of equipment is greater than the firstpredetermined mpy value (e.g., 3 mpy) and less than or equal to a secondpredetermined mpy value (e.g., 5 mpy), and with at least one of a thirdtext (e.g., “ACCELERATED RATE”) and a third color (e.g., red) for anaccelerated corrosion rate if the rate of corrosion for the monitoredpiece of equipment is greater than the second predetermined mpy value(e.g., 5 mpy). In some embodiments, the corrosion rate value can bedisplayed in mpy. The at least one client device can be at least one ofa mobile device and a stationary electronic device.

In some embodiments, at least one client device (e.g., user device,portable electronic device) displays the information related to at leastone of the calculated level of corrosion and the calculated rate ofcorrosion to a user. The displayed information can be displayed as anindication of severity of corrosion of the monitored piece of equipmentin at least one of a text format and a color format. For example, theindication of severity of corrosion is displayed with at least one of afirst text (e.g., “NORMAL RATE”) and a first color (e.g., green) for anormal corrosion rate if the rate of corrosion for the monitored pieceof equipment is less than or equal to a first predetermined mills peryear (mpy) value (e.g., 0 to 3 mpy), with at least one of a second text(e.g., “INTERMEDIATE RATE”) and a second color (e.g., yellow) for anintermediate corrosion rate if the rate of corrosion for the monitoredpiece of equipment is greater than the first predetermined mpy value(e.g., 3 mpy) and less than or equal to a second predetermined mpy value(e.g., 5 mpy), and with at least one of a third text (e.g., “ACCELERATEDRATE”) and a third color (e.g., red) for an accelerated corrosion rateif the rate of corrosion for the monitored piece of equipment is greaterthan the second predetermined mpy value (e.g., 5 mpy). In someembodiments, the corrosion rate value can be displayed in mpy. The atleast one client device can be at least one of a mobile device and astationary electronic device.

At least one aspect relates to a sensor assembly for a corrosionmonitoring device to monitor corrosion in a pipe of a fire sprinklersystem. The sensor assembly includes at least one corrosion sensorportion, a plug insert, and a housing. The at least one corrosion sensorportion has a coupon portion that corrodes in an environment of a wallof a pipe at a rate corresponding to at least one of a corrosion leveland a rate of corrosion of the wall based on an electricalcharacteristic of the at least one corrosion sensor portion. The couponportion is cylindrical. The plug insert receives the at least onecorrosion sensor portion. The housing receives the plug insert.

At least one aspect relates to a corrosion monitoring system formonitoring corrosion in a pipe of a fire sprinkler system. Themonitoring device has at least one corrosion sensor. The monitoringdevice monitors the pipe and determines corrosion data corresponding tocorrosion of the pipe, the corrosion status based on an electricalcharacteristic of the at least one corrosion sensor. The calculationdevice has a corrosion rate circuit that receives the corrosion datafrom the monitoring device and calculates at least one of a level ofcorrosion and a rate of corrosion of the pipe based on the corrosiondata. At least one client device presents display data regarding the atleast one of the calculated level of corrosion and the calculated rateof corrosion, the at least one receives the at least one of thecalculated level of corrosion and the calculated rate of corrosion via acommunication network that exchanges information between the calculationdevice and the at least one client device.

At least one aspect relates to a method of monitoring corrosion in apipe of a fire sprinkler system using a corrosion monitor. The methodincludes determining, by a monitoring device using at least onecorrosion sensor, corrosion data corresponding to corrosion of the pipebased on an electrical characteristic of the at least one corrosionsensor. The method includes calculating, by a corrosion rate circuit ofa calculating device, at least one of a level of corrosion and a rate ofcorrosion for the pipe based on the corrosion data. The method includespresenting, by at least one client device, display data regarding the atleast one of the calculated level of corrosion and the calculated rateof corrosion.

These and other aspects and implementations are discussed in detailbelow. The foregoing information and the following detailed descriptioninclude illustrative examples of various aspects and implementations,and provide an overview or framework for understanding the nature andcharacter of the claimed aspects and implementations. The drawingsprovide illustration and a further understanding of the various aspectsand implementations, and are incorporated in and constitute a part ofthis specification.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are not intended to be drawn to scale. Likereference numbers and designations in the various drawings indicate likeelements. For purposes of clarity, not every component can be labeled inevery drawing. In the drawings:

FIG. 1A is a perspective view of a sensor assembly;

FIG. 1B is a side view of a sensor assembly;

FIG. 1C is a top view of a sensor assembly;

FIG. 1D is a side cross-sectional view of a sensor assembly;

FIG. 2A is a perspective view of a plug insert of a sensor assembly;

FIG. 2B is a top view of a plug insert;

FIG. 2C is a side cross-sectional view of a plug insert;

FIG. 3A is a perspective view of a housing of a sensor assembly;

FIG. 3B is a side cross-sectional view of a housing;

FIG. 4 is a perspective view of a temperature sensor;

FIG. 5A is a perspective view of a sensor assembly;

FIG. 5B is a side view of a sensor assembly;

FIG. 5C is a top view of a sensor assembly;

FIG. 5D is a side cross-sectional view of a sensor assembly;

FIG. 6 is a block schematic view of a monitoring device;

FIG. 7 is a schematic view of an exemplary relay circuit of a monitoringdevice;

FIG. 8 is a flow diagram of a method of determining when a freeze alertshould be issued to be executed by a temperature monitoring circuit of amonitoring device;

FIGS. 9A and 9B are arrangements of a monitoring device in “dry-pipe”and “wet-pipe” systems, respectively;

FIG. 10 is an example of an operating environment in which a monitoringdevice can be utilized;

FIG. 11 is a block diagram of a processing circuit set associated with acorrosion monitoring system and a gateway unit capable of receivingtransmissions from one or more processing circuits;

FIG. 12 is a block diagram of a monitoring platform; and

FIG. 13 is a flow diagram of a method of determining when to transmit anotification to a monitoring platform that the equipment being monitoredis not fully operative.

DETAILED DESCRIPTION

The present disclosure generally relates to monitoring of equipment incorrosive or potentially corrosive environments. More particularly, thepresent disclosure relates to systems, methods, and sensor devices usedto remotely monitor corrosion, including the current level of thecorrosion and the rate of corrosion, of equipment in a corrosiveenvironment. The equipment being monitored can be, for example, pipes inpiping systems (e.g., in fire suppression systems), which are pervasivein a variety of businesses, from restaurants to hotels. The level of thecorrosion of a piece of equipment relates to the amount of corrosion theequipment has experienced (e.g., weight loss per area, loss of thicknessof the metal, or some other measure of corrosion). In addition,measuring the rate of corrosion will help predict when a portion of theequipment (e.g., pipe walls) will be so thin that there is highlikelihood of failure, e.g., leaks, and/or there could be a buildup thatcan cause blockage. Thus, measuring the rate of corrosion gives the useror business time to schedule maintenance instead of performing emergencymaintenance on the piping systems. Accordingly, collecting the level ofthe corrosion and the corrosion rates will also help notify the user orbusiness of potential problems (e.g., blockages and/or leaks in thepipes) caused by the corrosion.

In some instances, because there is no way to completely eliminate thecorrosion process, in time, the corrosion of the components in a systemcan lead to damage and potential catastrophic failure. Although thereare techniques to minimize the corrosion process, e.g., using asacrificial layer/coating on metals, using chemical inhibitors, and/orusing inert gases to displace the oxygen in the system, there arecurrently no methods to completely stop the corrosion process. Forexample, corrosion of pipes in a fire sprinkler system can result inblockage of pipes and/or leaks that can lead to temporary shutdowns ofthe systems, reduced effectiveness of fire sprinkler design, total firesprinkler replacement, loss of property due to a failure in which thefire sprinkler system fails to protect the equipment it is designed tosafeguard, loss of production, and potential personal injury.

There are typically two main causes of corrosion: generalized corrosion(red/black rust) and microbiologically influenced corrosion (MIC).Generalized corrosion is commonly known as rust and requires water,iron, and oxygen for the rust reaction. MIC refers to corrosion due tothe presence and activities of bacteria. There are three main types ofbacteria, which are acid producing bacteria (APB), sulfur reducingbacteria (SRB), and iron related bacteria (IRB). Studies indicate that40% of corrosion is influenced by MIC and 60% is general corrosion.Corrosion can flourish even in dry pipes such as in dry-type firesprinkler systems because these pipes are never 100% dry. Trapped waterand/or humid air from air compressors can create the perfect conditionsfor corrosion to occur.

Some systems can monitor corrosion to help predict failures before theyoccur. Some systems provide an in-line detection system in which thecorrosion detector replaces a section of pipe. The corrosion detectorcan include an inner pipe wall that is designed to fail first (e.g., theinner wall can be thinner than the actual pipe wall). A failure of theinner wall of the corrosion detector will trigger a pressure switch thatcan activate an alarm. However, such systems may not measure the leveland/or rate of corrosion, which can predict when a pipe failure islikely to occur, and require that a section of the pipe be cut in orderto install the detector. Further, different types of detectors may berequired for “wet systems” in which the pipes are always filled withwater and “dry systems” in which the pipes are not filled with wateruntil the fire system is activated. Some corrosion detector systems usecoupons made of the relevant material such as steel, brass, copper, orsome other relevant material that are inserted into the piping system.The coupon can be attached to a test plug such as an NPT fitting.However, such systems may require that the coupon be removed andanalyzed, e.g., shipped to a lab for testing, on a periodic basis.Accordingly, such systems may not provide continuous remote monitoringof the piping. In some systems, a coupon is incorporated into the NPTplug and a visible display on the NPT plug changes color once apredetermined amount of the coupon corrodes away. Such systems, however,also cannot provide continuous remote monitoring of the piping. Inaddition, corrosion detection devices may only monitor corrosion and donot provide other useful information such as the temperature of theequipment environment or the presence of water in the equipmentenvironment.

In addition to the level and/or rate of corrosion, the temperature ofthe equipment environment, ambient temperature outside the equipmentbeing monitored, and/or the presence or absence of water in theequipment can also provide useful information. For example, collectinglive temperature readings inside and outside the pipes of the pipingsystem can aid in determining whether there is the potential for thepipes to freeze, an issue that might go undetected until a leak (orleaks) occurs once the piping system starts to thaw. In addition, infire suppression systems, a frozen pipe can also impede the flow ofwater when the fire system is activated, potentially leaving the firesprinkler system useless. Further, the presence of water in a “dry”piping system can mean there are potential maintenance issues (e.g., aleaking valve) that need to be resolved. Accordingly, along withdetermining the level and/or rate of corrosion, solutions describedherein can sense the temperature of the equipment environment, theambient temperature, and/or the presence or absence of water in thepipe. For example, sensor assemblies can include corrosion sensors,temperature sensors, and water presence sensors. In the case of a firesuppression system, determining the corrosion levels and/or rates,temperatures inside/outside a pipe in the piping system, and/or thepresence or absence of water in the pipe provides for well maintainedand functional piping systems and will provide for a lifesavingsprinkler system.

The techniques introduced here for monitoring corrosion, water presenceand/or temperature can be embodied as special-purpose hardware (e.g.,circuitry), as programmable circuitry appropriately programmed withsoftware and/or firmware, or as a combination of special-purpose andprogrammable circuitry or hardware. For example, some embodiments canutilize a programmable microprocessor made by MultiTech MultiConnect®xDot™ that communicates over a LoRaWAN network. Hence, embodiments mayinclude a machine-readable medium having stored thereon instructionsthat may be used to program a computer (or other electronic devices) toperform a process. The machine-readable medium may include, but is notlimited to, floppy diskettes, optical disks, compact disc read-onlymemories (CD-ROMs), magneto-optical disks, read-only memories (ROMs),random access memories (RAMs), erasable programmable read-only memories(EPROMs), electrically erasable programmable read-only memories(EEPROMs), magnetic or optical cards, flash memory, or other type ofmedia/machine-readable medium suitable for storing electronicinstructions.

FIGS. 1A 1B, 1C, and 1D respectively depict a perspective view, a sideview, a top view, and a cross-sectional view of a sensor assembly. Asdepicted in FIGS. 1A-1D, sensor assembly 2 includes a plug insert 3 anda housing 4. The plug insert 3 can be a separate component from housing4 and disposed in the housing 4. The plug insert 3 can be secured in thehousing 4 via a press fit. The plug insert 3 can be secured housing 4using a threaded connection. The plug insert 3 and the housing 4 can beintegral. The sensor or sensors of sensor assembly 2 can be disposed inthe plug insert 3. The sensor assembly 2 can include one or morecorrosion sensors having a geometric shape that permits determination ofinformation relating to at least one of a corrosion level and a rate ofcorrosion of the monitored equipment based on an electricalcharacteristic of the at least one corrosion sensor. The corrosionsensors can be coupon portions 6 that form at least part of wire loop 5.The ends of the wire loops 5 can be attached, e.g., by soldering oranother means of attachment, to wire leads that are then routed outsidethe housing 4 of the sensor assembly 2. Depending on the type of sensorassembly, the sensor assembly 2 can include an equipment environmenttemperature sensor 20, an ambient temperature sensor (not shown), or anycombination of the temperature sensors the one or more corrosionsensors. The leads from the wire loops 5 and the temperature sensors canbe connected to a monitoring circuit as discussed below.

FIGS. 2A-2C respectively depict a perspective view, a top view, and across-sectional view of a plug insert 3. The plug insert 3 can be asingle unitary structure, such that the plug insert 3 is not an assemblyof two or more components. As depicted in FIGS. 2A-2C, the four wireloops 5 having coupon portions 6 (see FIG. 1A) can be installed inlongitudinal openings 12 (see FIGS. 2A-2C) that extend the entire lengthof plug insert 3. The coupon portions 6 are exposed to the corrosiveequipment environment and the leads of the wire loops 5 that extend fromthe coupon portions are embedded in the plug insert 3 to protect theleads from the corrosive equipment environment. The cross-section ofeach of the longitudinal openings 12 corresponds to the cross-section ofthe wire loop leads of the corrosion sensors 6 that pass throughopenings 12. The insert plug 3 can receive a temperature sensor thatmeasures a temperature of the equipment environment such as, forexample, the inside environment of a pipe. For example, as depicted inFIGS. 2A-2C, the plug insert 3 can include a recessed portion 8 that canreceive a temperature sensor 20 such as a thermistor. As depicted inFIG. 4, the temperature sensor 20 can include a sensor portion 20A andleads 20B that can be routed outside the sensor assembly 2. As depictedin FIG. 2C, to accommodate the temperature sensor 20, the recessedportion 8 can have a step profile in which an outer cavity 8 a stepsdown to an inner cavity 8 b that is smaller, e.g., in diameter, than theouter cavity 8 a. The inner cavity 8 b is sized to receive and hold thehead 20 a of the temperature sensor 20. The temperature sensor 20 can beheld in the inner cavity 8 b using a press fit. The temperature sensor20 can be attached to the recessed portion 8 using at least one of athreaded connection, an adhesive, and a bonding agent. The outer cavity8 a provides protection for the head 20 a while still allowing thetemperature sensor 20 to sense the equipment environment, e.g., theinside of a pipe, and thus ensure accurate temperature readings of theequipment environment. The step profile can further include a step downfrom cavity 8 b to a passage 8 c that is smaller, e.g., in diameter,than cavity 8 b. The passage 8 c provides a passageway for the sensingleads 20 b from temperature sensor 20 to exit the plug insert 3.Appropriate sealing, e.g., epoxy, can be used to fluidly isolate therecessed portion 8 from the outside of the sensor assembly 2. Dependingon the design of the temperature sensor 20, the plug insert 3 can havevarious recess profiles to accommodate a specific temperature sensorconfiguration. Along with helping to protect the temperature sensor 20,the recess portion 8 can allow for the corroding metal from couponportions 6 to migrate so that the coupon portions 6 are not affected bya buildup of corroded metal. The plug insert 3 can have a low electricalconductivity and/or a low thermal conductivity. The plug insert 3 can bemade of a plastic. The plug insert 3 can be composed of a thermosetmaterial, such as a thermoset material that is in compliance with theUnderwriter Laboratories (UL) standards concerning fire suppressionsystems. For example, the plug insert 3 can be composed of a siliconmaterial, urethane material, another type of thermoset material, or anycombination thereof. The plug insert 3 can be made of a thermoplasticsuch as an acrylonitrile butadiene styrene (ABS) plastic. Thecomposition of the plug insert 3 can be made of a metal or metal alloy,a thermoset plastic, a thermoplastic, a ceramic, or a combinationthereof. The plug insert 3 or the housing 4 can be made of a materialthat is non-conductive electrically. The plug insert 3 or the housing 4can be made of a material that is rated to at least 250 deg. F.

As depicted in FIGS. 3A and 3B, the housing 4 of the sensor assembly 2can receive the plug insert 3. The housing 4 can be in the shape of ahollowed out plug with an opening 9 extending through the longitudinalaxis of the housing 4. In some systems such as, e.g., fire suppressionsystems, to limit the leakage of fluid (e.g., air or water) from insidethe pipe to the outside, the cross-sectional of opening 9 is limited byhaving a plurality of small openings respectively corresponding to thewire loops 5 and temperature sensor 20. In some embodiments, theopenings have an area of 0.10 square inches or less. Housing 4 caninclude threaded section 6 for securing the sensor assembly 2 to acorresponding fitting on the equipment to be monitored, e.g., a threadedpipe end in a fire sprinkler system. The housing 4 can include a headportion 7 that is configured to facilitate the installation of thesensor assembly 2 in the equipment being monitored. The housing 4 can bein the shape of a threaded pipe plug, such as the shape of a standardthreaded pipe plug. For example, the housing 4 can be in the shape of a1 inch National Pipe Thread (NPT) threaded pipe plug (or some otherstandard pipe plug size) with a head portion 7 that is hexagonal inshape or some other shape that facilitates installation using a tool(e.g., a hex socket). The housing 4, including head portion 7, can havevarious shapes as appropriate for the equipment being monitored. Thehousing 4 can be made of a metal or a metal alloy, such as being made ofa metal or a metal alloy that is more resistant to corrosion than theequipment being monitored. The housing 4 can be made of the samematerial as the equipment being monitored. The composition of thehousing 4 can be made of a metal or metal alloy, a thermoset plastic, athermoplastic, a ceramic, or a combination thereof, as appropriate. Thehousing 4 and the plug insert 3 can be one integrated unit. Theintegrated housing 4 and plug inset 3 can be injection molded. Thecomposition of the integrated housing 4/plug 3 can be made of a metal ormetal alloy, a thermoset plastic, a thermoplastic, a ceramic, or acombination thereof, as appropriate. The housing 4 can be rated for thesame or higher pressures and temperatures as the equipment beingmonitored. The housing 4 can be rated at 2 to 3 times the operatingpressure of the equipment being monitored. In the case of piping systemsfor fire sprinklers, the equipment typically operates from 150 psi to175 psi; for example, the housing 4 can be rated is a range from 300 psito 525 psi. For example, in some embodiments, such as a typical pipingsystem for fire sprinkler systems, the threaded pipe plug is rated up to400 psi. Of course, the pressure rating is dependent on the applicationand, in some embodiments, the housing 4 can be a pipe plug that is ratedup to 1600 psi, such as being rated up to 3000 psi.

In some embodiments, where the the housing 4 is sufficiently large, allor part of the components associated with the control circuit for sensorassembly 2 (e.g., the power source 112, the monitoring and conversioncircuit 110, and/or the transmitter circuit 116 of control unit 104discussed below) can be disposed in the housing 4 along with or as partof the plug insert 3. The housing 4, sensor assembly 2 and/or one ormore components of the control circuit (e.g., control unit 104) can forman integral device. For example, the coupon portions 6 and/ortemperature sensors 20 and/or 25 and/or one or more components ofcontrol unit 104 can be embedded into a plastic plug, e.g., via aninjection molding process, that is in the shape of a threaded pipe plug.Whether the outer housing is a separate component or integral to thesensing assembly (and/or one or more components of the control unit104), the coupon portions 6 are exposed to the corrosive environmentthat the equipment is exposed to. For example, as discussed furtherbelow with respect to FIGS. 9A and 9B, when installed in the pipe 150,the coupon portions 6 a-6 d can be exposed to the internal environmentalof the pipe 150 so that the monitoring device 100 can monitor the rateof corrosion of the wall of pipe 150 as discussed in more detail below.

As discussed above, the sensor assembly 2 can include one or more wireloops 5 that are disposed in the plug insert 3. Although four wire loops5 a-5 d are depicted in FIGS. 1A-1D, the sensor assembly 2 can have anynumber of wire loops 5 such as, e.g., one, two, three, four, or morewire loops 5. Each of the wire loops 5 a-5 d can respectively include acoupon portion 6 a-6 d that is configured to corrode. At least thecoupon portion 6 a-6 d of each of the wire loops 5 a-5 d can be exposedto the same corrosive environment that the monitored equipment isexposed to. For example, in an application of a piping system where theinterior of a pipe 150 (see FIGS. 9A and 9B) is monitored for corrosion,the coupon portion 6 can be exposed to the interior of the pipe 150. Thesensor assembly 2 can be mounted in a horizontal section of the pipe150. The sensor assembly 2 can be mounted in a vertical section of thepipe 150 and/or in a slanted section of the pipe 150. The couponportions 6 a-6 d can be made of material that is the same as theequipment being monitored, e.g. the same material as the interior wallmaterial of pipe 150, so that a rate of corrosion of the coupon portion6 a-6 d matches a rate of corrosion of the equipment being monitored.For example, for a carbon-steel pipe, the coupon portions 6 a-6 d can bemade of the same carbon-steel material. For a black steel pipe, thecoupon portions 6 a-6 d can be made of the same black steel material.one or more of the coupon portions 6 may not made of the same materialas the equipment being monitored, but instead made of a material wherethe level of corrosion of the coupon portion can still be correlated tothe level of corrosion (e.g., weight loss per area, loss of thickness,or some other measure of corrosion) of the monitored equipment and/orthe rate of corrosion of the coupon portion can still be correlated tothe rate of corrosion (e.g., mpy or mmy) of the monitored equipment. Inthe case of coated equipment such as coated pipes, the coupon portion 6can be made of the base metal and not coated so as to provide an earlyindication of potential corrosion problems. The coupon portion 6 can becoated to match the coating on the equipment being monitored. Forexample, if the equipment being monitored is galvanized, the couponportion 106 can be galvanized.

At least one coupon portion 6 has a different thickness or diameter thanthe other coupon portions 6. In some embodiments, each of the couponportions 6 a-6 d has a different thickness or diameter than the othercoupon portions 6. The shape or geometry of the coupon portion 6 is notlimiting so long as the measured level and/or rate of corrosion can becorrelated to the level and/or rate of corrosion of the equipment beingmonitored with respect to the pertinent parameter such as, e.g., thethickness of a pipe wall. For example, where the continuity of thecoupon 6 is being monitored, such as whether the coupon 6 open circuitedor not, the shape or geometry of the coupon 6 should be such that thecoupon portion 6 loses continuity (e.g., opens) prior to the equipmentbeing monitored reaching an unsatisfactory state. For example, thecoupon can lose continuity (open) prior to the walls of a pipe thinningto a point where failure has occurred or is imminent. The coupon portion6 can have a uniform shape with respect to the exposed surface area,e.g., a uniform thickness with respect to the exposed surface area. Ageometric shape of the coupon portion 6 can include a portion having aconstant diameter (uniform thickness) such as, e.g., a cylindricalshape. The orientation of the coupon portion 6 can be such that theentire surface area of the coupon portion 6 is exposed to the corrosiveenvironment. For example, if there is not enough of a gap between thecoupon portion 6 and the top surface of the plug 3 and/or if there isnot enough gap between a coupon portion 6 and another component (e.g.,another coupon portion, wall of the sensor assembly, or anothercomponent), as the metal from coupon portion 6 corrodes and migrates, abuildup of the corroded material can potentially block (either partiallyor entirely) the coupon portion 6 from the corrosive environment. Whenthis occurs, the coupon portion 6 can give false readings with respectto the monitored electrical characteristic. For example, the continuitycan indicate closed when the coupon portion 6 is actually open. Thecoupon portion 6 can be disposed or oriented such that the entiresurface area of the coupon portion 6 remains exposed to the corrosiveenvironment for the life of the coupon portion 6.

Coupon portion 6 is not limited to a specific diameter or thickness.Generally, a smaller diameter/thickness coupon is used when a fastercorrosion reading is desired. The coupon portion 6 can have a diameteror thickness that is in a range from about 0.003 inches to 0.050 inches.At least one coupon portion 6 can have a surface area that is differentfrom the surface areas of the other coupon portions 6. In someembodiments, each coupon portion has a surface area that is differentfrom the other coupon portions. A difference in the diameter orthickness of a given coupon portion 6 and a diameter or thickness of thenext larger coupon portion 6 can be in a range from about 0.002 inch toabout 0.035 inch. When four coupon portions 6 a-6 d are used, thediameters or thickness can be within ±10% of 0.014 inch, 0.018 inch,0.0347 inch, and 0.047 inch, respectively. The diameters and thicknesscan depend on the equipment being monitored, the required or preferredresolution on the level/rate of corrosion, the preferred notice time forthe corrosion, or some other criteria. For example, because a percentagechange in the resistance of a thinner coupon portion 6 will be greaterthan a thicker coupon portion 6, if a user requires a higher resolutionand/or an early alarm (early notice time) on the onset of any measurablecorrosion, at least one of the coupon portions 6 may be configured to bemuch thinner than the rest.

If a coupon portion 6 having the smallest thickness or diameter hascorroded to a point where the corresponding wire loop 5 open circuits(e.g., breaks), the other wire loops 5 can still be closed to provide anindication of the level and/or rate of corrosion of the equipment beingmonitored going forward. Accordingly, by providing coupon portions 6with different thicknesses or diameters, the control circuit connectedto the sensor assembly 2 (e.g., control circuit 104 discussed furtherbelow) can monitor the corrosion of the equipment, e.g., the wall ofpipe 150, over an extended period of time. That is, when one couponportion 6 breaks, a corrosion level and/or rate can be calculated.Because their thicknesses or diameters are larger, the other couponportions 6 can remain intact, and thus there is no need to immediatelyreplace the sensor assembly 2. The thickest coupon portion 6 can besized such that the sensor assembly 2 need not be replaced for 10 to 15years. This can be advantageous for monitoring the piping in firesystems, which typically last 50 to 100 years. By appropriatelyconfiguring the number and thicknesses/diameters of the coupons, thenumber of times a sensor assembly needs to be replaced can be minimized.In some embodiments, the coupon portions 6 a-6 d are sized such that thelifetime of the sensor assembly 2 is approximately the same as or longerthan the lifetime of the equipment being monitored.

In some embodiments, the use of coupon portions 6 with differentthicknesses or diameters allows for the rate of corrosion to beprecisely tracked throughout the entire time period that the equipmentis being monitored. For example, the coupon portions 6 can be configuredsuch that, as the thinnest of coupon portions 6 open circuits due tocorrosion or has reached a point where the change in resistance of thecoupon portion cannot be accurately correlated to the level and/or rateof corrosion of the equipment, the next thinnest of coupon portions 6reaches a thickness or diameter where the accuracy of the change inresistance readings is equal to or substantially equal to the originalthickness or diameter of the coupon portion that just open circuited.This process can continue for the remaining coupon portions 6. That is,the thickness or diameter of the next thinnest remaining coupon portion6 can be the same or substantially the same as (e.g., within ±25%) theoriginal thickness or diameter of the thinnest coupon portion 6. In thisway, the control circuit monitoring the sensor assembly 2 can accuratelytrack the level and/or rate of corrosion of the equipment beingmonitored over an extended period of time when compared to having justone wire loop 5 that is initially very thick. By accurately monitoringthe corrosion rate over an extended period of time, any change in thelevel and/or rate of corrosion can also be detected and brought to auser's attention, if necessary, as the coupon portions 6 corrode away.

FIGS. 5A-5D depict a sensor assembly including wire loops 5′ andtemperature sensor 20′. In the embodiment of FIGS. 5A-5D, the pluginsert 3′ is made of multiple components, e.g., cap 3A′, insert body3B′, and connection end 3C′, that are assembled together to form theplug insert 3′. Wire loops 5′ can include a coupon portion 6′ and aconnection portion 11′. For example, the wire loops 5 a′-5 d′ caninclude respective coupon portions 6 a′-6 d′ and connection portions 11a′-11 d′. The connection portions 11 a′-11 d′ electrically connectcoupon portions 6 a′-6 d′ to a control circuit (e.g., control unit 104discussed further below) that monitors an electrical characteristic ofthe coupon portions 6 a′-6 d′. In some embodiments, the coupon portions6 a′-6 d′ can connect directly to the control unit, such that there isno separate connector such as connectors 11 a′-11 d′. The connectionportions 11 a′-11 d′ can be not exposed to the corrosive environment,e.g., the interior of the pipe, so that the connection portions 11 a′-11d′ do not corrode. The connection portions 11 a′-11 d′ can be made of amaterial that does not corrode as fast as the coupon portions 6 a′-6 d′.For example, the connection portions 11 a′-11 d′ can be gold plated toensure that the coupon portions 6 a′-6 d′ corrode well before theconnection portions 11 a′-11 d′. The resistance of the connectionportions 11 a′-11 d′ may not significantly change as the coupon portions6 a′-6 d′ corrode. In some embodiments, the connection portions 11 a′-11d′ are spring-loaded pogo pin-type connectors. The springs can accountfor any movement of the coupon portions 6 a′-6 d′ due to corrosion ofthe coupon portions 6 a′-6 d′.

FIG. 6 depicts a schematic block diagram of a monitoring device 100. Themonitoring device 100 can include a sensor assembly 102 with corrosionsensors and/or temperature sensors and a control unit 104 that monitorsthe sensor assembly 102. The sensor assembly 102 can incorporatefeatures of e.g., sensor assembly 2 or sensor assembly 2′ discussedabove. As depicted in FIG. 6, the control unit 104 can include amonitoring and conversion circuit 110. The corrosion sensors in sensorassembly 102 can be coupon portions 106 that corrode at a rate that canbe correlated to a rate of corrosion of the monitored equipment. Themonitoring and conversion circuit 110 can monitor an electricalcharacteristic of the coupon portion 106. Wire loop 105 can be, e.g.,wire loop 5 or wire loop 5′ discussed above, and coupon portions 106 canbe coupon portions 6 or coupon portions 6′ discussed above. In someembodiments, a change in the electrical characteristic is alsodetermined from a previously determined electrical characteristic. Thechange in the electrical characteristic can be a change in the actualvalue of the monitored electrical characteristic and/or a percentagechange in the value of the monitored electrical characteristic.

The monitoring and conversion circuit 110 can provide currents thatrespectively flow through coupon portions 106A-106D of the respectivewire loops 105A-105D. In some embodiments, the monitoring andconversation circuit 110 can include a corrosion detector circuit 132 tomeasure the electrical characteristic of the wire loop 105 and/or thecoupon 106 and determine information related to at least one of thecorrosion level and the rate of the equipment being monitored based onthe measured electrical characteristic. The corrosion detector circuit132 can determine the information related to the at least one of thecorrosion level and the rate of equipment as a corrosion status. Theelectrical characteristic being monitored by the corrosion detectorcircuit 132 can be a voltage of the coupon portion 106 and theinformation being determined is whether coupon portion 106 and thus wireloop 105 has continuity or not, e.g., still forms a closed loop or hasopen circuited. For example, FIG. 7 depicts a relay circuit 130 thatincludes a voltage divider circuit 162 that can be used for determininga corrosion state of the coupon 106. The voltage divider circuit 162includes relays K1-K4, a voltage source providing a voltage V_(IN), anda reference resistor R_(REF1) having a predetermined resistance.Reference resistor R_(REF1) also serves as a pull-down resistor to keepthe voltage V_(C) from floating when the respective coupon portion 106has corroded open and/or when relays K1-K4 are de-energized. Each relayK1-K4 can be operated, e.g., by a microprocessor (not shown) or othercircuit, which can be part of the monitoring and conversation circuit110. The microprocessor or other circuit can be part of the relaycircuit 130. Each coupon portion 106 a-106 d can be respectivelyconnected to the contacts corresponding to relays K1-K4. The couponportions 106 a-106 d can be selectively connected. The coupon portions106 a-106 d serve as the other “resistor” of the voltage divider circuit162 when each relay K1-K4 is selectively operated. Based on the relayK1-K4 that is operated, a predetermined known voltage V_(IN) is appliedto one end of the corresponding coupon portion 106 a-106 d and a voltageV_(C) can be read at the other end of the coupon portion 106 a-106 d.The voltage V_(C) can be transmitted to and measured by the detectorcircuit 132. For example, when relay K1 is energized, a voltage V_(IN)is applied to one end of coupon portion 106 a via terminal K1-3 of relaycontact K1A, and the voltage V_(C) is read by corrosion detector circuit132 via terminal K1-9 of relay contact K1B. Similarly, as relays K2-K4are selectively energized, the corresponding voltage V_(C) values forcoupon portions 106 b-106 d are transmitted to and read by corrosiondetector circuit 132. The voltage V_(C) value measured by the corrosiondetector circuit 132 is then read by the corrosion conversion circuit134 to determine if the appropriate coupon portion 106 has opencircuited due to corrosion or if there is still some continuity. TheV_(IN) value can be predetermined. In some embodiments, the value ofV_(IN) is stored in memory in the monitoring and conversion circuit 110(or some other appropriate place) and accessible to the corrosiondetector circuit 132 so that a separate measurement of V_(IN) is notrequired. The V_(IN) value can be measured by the corrosion detectorcircuit 132 when calculating the ratio V_(C)/V_(IN). In someembodiments, the stored value of V_(IN) can be updated either manuallyor automatically updated based on any variance in the V_(IN) value,e.g., due to the output of power source 112 starting to drop. Thecorrosion detector circuit 132 can compare the ratio V_(C)/V_(IN) to apredetermined value that corresponds to lack of continuity, i.e., anopen circuit. In some embodiments, the value of V_(IN) is the same asthe voltage supplied to the relay circuit 130 and the analog to digitalconversion circuit (ADC) in corrosion detector circuit 132. Because thesame reference voltage is used for the ADC and the relay circuit 130,the measure voltage V_(C) can be directly compared to a predeterminedvalue that corresponds to lack of continuity, e.g., an open circuit.

For example, if the ratio is above the predetermined value, thecorrosion detector circuit 132 determines that the corresponding couponportion 106 has continuity, e.g., coupon portion 106 is not broken, andif the ratio is equal to or below the predetermined value, the corrosiondetector circuit 132 determines that the corresponding coupon portion106 is open, e.g., that the coupon portion 106 has corroded to a pointthat there is a complete physical break and the wire loop 105 has opencircuited. In some embodiments, rather than a ratio, the measuredvoltage V_(C) can be directed compared to a predetermined value. Thepredetermined value for determining whether there is an open circuit(whether for comparison with a ratio or directly to V_(C)) can bedifferent based on whether the sensor assembly 102 is wet or dry. If wet(e.g., the sensor assembly 102 is in water), a current can still flowthrough the water to complete the current loop even after the couponbreaks, but V_(C) will be lower due to the increased resistance of thecurrent path through the water. If dry (e.g., the sensor assembly 102 isnot in water), V_(C) will be zero. Accordingly, the predetermined valuecan depend on whether the sensor assembly 102 is wet or dry. In someembodiments, the predetermined value is the same regardless of whetherthe sensor assembly 102 is wet or dry. The determination of whethercoupon 106 has corroded open or not can be used in determining the leveland/or rate of corrosion of the equipment being monitored. Thedetermination of the level and/or rate of corrosion can be done in themonitoring and conversion circuit 110 and/or on a remote server orcomputer.

The corrosion detector circuit 132 can use various methods to determinewhether the coupon 106 still has continuity or has corroded open. Forexample, a constant voltage drop can be provided across the respectivecoupon portions 106 a-106 d and a current through the coupon portions106 a-106 d can be measured to determine whether there is an opencircuit. When the coupon 106 breaks due to corrosion, the currentthrough the respective wire loop 105 is lower or zero (depending onwhere the sensor assembly 102 is in water or not). Accordingly, in someembodiments, the measured current can be used to determine whether thecoupon 106 has corroded open. For example, similar to the embodimentdiscussed above, a ratio of the measured current to a reference current(e.g., the current through an un-corroded coupon) can be compared to apredetermined value or the actual measured current can be compared to apredetermined value. A constant current can be transmitted (orattempted) through the respective coupon portions 106 a-106 d and avoltage drop across the wire loop 105 a-105 d and/or the respectivecoupon portion 106 a-106 d can be measured to determine whether thecoupon portion 106 has corroded open. A ratio of the measured voltage toa reference voltage (e.g., the voltage across an un-corroded coupon) canbe compared to a predetermined value or the actual measured voltage canbe compared to a predetermined value; there will be a higher voltagedrop across coupon 106 as compared to an un-corroded coupon 106 when thecoupon 106 has corroded open.

In some embodiments, the measured voltage and/or current readings can beused to determine the actual corrosion level and/or rate prior to thecoupon portion 106 corroding open. For example, a change in the voltageand/or current measurements can be correlated to a change in thecorrosion of the coupon portion 106 (and thus the equipment beingmonitored) even before the coupon portion 106 has corroded open.

In some embodiments, the electrical characteristic can be a resistancevalue. For example, the voltage and/or current measurements discussedabove can be used to determine a resistance value of the coupon 106,which can then be correlated to level and/or rate of corrosion of theequipment being monitored. For example, the corrosion detector circuit132 can be configured to determine a resistance of the coupon 106. Thecorrosion detector circuit 132 can be configured to output a currentthrough each of the wire loops 105A-105D. The corrosion detector circuit132 can include a sensor to sense the current through at least one wireloop 105 (e.g., via known current sensors). The corrosion detectorcircuit 132 can provide a constant or near constant voltage drop acrossthe coupon portions 106 a-106 d such that the respective current througheach of the loops 105A-105D varies in time based on the amount ofcorrosion the respective coupon portions 106 a-106 d have experienced.For example, the coupon portions 106 are configured to corrode suchthat, as the coupon portions 106 a-106 d corrode, the current througheach wire loop 105 a-105 d changes due to a decrease in thecross-sectional area of each coupon portion 106 a-106 d, which increasesthe resistance in the respective coupon portion 106 a-106 d. Based onthe sensed value or values of each coupon portion 106 a-106 d, thecorrosion detector circuit 132 (or another device such as monitoringplatform 230—see FIG. 10) can calculate respective resistance values ofthe coupon portions 106 a-106 d, which can include instantaneousresistance values and/or averaged resistance values. In someembodiments, the corrosion detector circuit 132 can be configured tokeep the current through each wire loop 105A-105D constant while sensingthe voltage drop across each coupon portion 106 a-106 d. The measuredvoltage drop can then be correlated to a resistance value. The change inthe resistance values can then be correlated to a level and/or rate ofcorrosion of the equipment being monitored.

The electrical characteristic can be an inductance value of the coupon106. For example, the coupon 106 can be in the shape of a coil or someother shape that is appropriate for measuring inductance and the powerto the coupon 106 can be an AC waveform (e.g., pulsed sinusoidal, etc.),a pulsed DC waveform, a stepped waveform, and/or another non-constantwaveform. As the coupon 106 corrodes, its inductance will change, andthe measured change in inductance is correlated to a level and/or rateof corrosion of the equipment being monitored. Various characteristicsof the coupon portion 106 can be monitored so long as there is acorrelation to the corrosion in the equipment.

Regardless of the type of electrical characteristic being measured orthe sensing method being used (sensed voltage or sensed current), thei²r heating of the coupon portions 106 a-106 d may not adversely affectthe calculations and/or is taken into account when determining theelectrical characteristic of the coupon portions 106 a-106 d.

As depicted in FIG. 6, the monitoring and conversion circuit 110 caninclude a corrosion rate circuit 134 that receives the informationrelated to the corrosion level and/or the rate of the equipment beingmonitored from the corrosion detector circuit 132. Based on the receivedinformation, the corrosion rate circuit 134 correlates the informationregarding the electrical characteristic of the corrosion sensor 106 to alevel of the corrosion (e.g., weight loss per area, loss of thickness ofthe metal, or some other measure of corrosion) and/or a rate ofcorrosion (e.g., mpy or mmy) of the equipment being monitored, e.g., thewall of pipe 150. For example, if the corrosion detector circuit 132determines that a coupon portion 106 has opened, e.g., the continuity ofthe coupon portion has changed from having continuity to open (nocontinuity), the corrosion detector circuit 132 sends information to thecorrosion rate circuit 134 that the appropriate coupon portion 106 hasan open circuit status. The corrosion rate circuit 134 receives thestatus information from the corrosion detector circuit 132 andcalculates the corrosion weight loss for the appropriate coupon potion106. As an example, for a coupon portion having a 0.014 inch diameter, adensity of 7.85 grams/cm³, and an exposed area of 0.012 square inches,when the status of that coupon portion shows an open circuit, thecorrosion rate circuit 134 will determine that the weight loss of thecoupon portion is 0.005 grams. For each coupon size, the weight loss atthe time that the coupon portion 106 has an open status can bedetermined empirically. The corrosion rate circuit 134 can correlate theweight loss per area of the coupon portion 106 to the weight loss perarea of the equipment being monitored, e.g., the weight loss per area ofthe wall of pipe 150. These correlations can be determined empirically(e.g., the correlation between change in the electrical characteristicto the estimated loss of weight per area of the coupon portion and thecorrelation between the estimated loss of weight per area of the couponportion and the estimated loss of weight per area of the equipment canbe determined empirically). When the coupon portion 106 is made of thesame material as the equipment being monitored, the weight loss per areaof the coupon portion 106 will be the same (e.g., within ±25%) of theweight loss per area of the equipment being monitored, e.g., the wall ofpipe 150. Based on the calculated weight loss per area (either of thecoupon portion 106 or the equipment being monitored), in someembodiments, the corrosion rate circuit 134 can calculate the corrosionrate (CR) in, e.g., mils per year (mpy) or another measure. Based on theappropriate weight loss value (coupon or equipment) determined above,the corrosion rate (CR) of either the coupon portion 106 or theequipment being monitored can be calculated using the equation: CR=(WL*K)/(D*A*ET); where WL is weight loss (e.g., grams); D is alloydensity (e.g., g/cm³); A is exposed area (e.g., in², cm²); ET isexposure time (e.g., hours); and K is 5.34*10⁵ for calculating mpy whenA is in², 3.45*10⁶ for calculating mpy when A is cm², and 8.76*10⁴ forcalculating mmy when A is cm². The exposure time ET can be based on astart time stamp corresponding to when the sensor assembly 102 isinstalled and an end time stamp corresponding to when the corrosiondetector circuit 132 measured the electrical characteristic. Thecorrosion rate circuit 134 can categorize the severity of the corrosionbased on the calculated corrosion rate. For example, the corrosion ratecircuit 134 can categorize a CR value in arrange from 0 to 3 mpy as“NORMAL CORROSION RATE,” a CR value in a range from above 3 to 5 mpy asan “INTERMEDIATE CORROSION RATE,” and a CR value in a range from above 5mpy as an “ACCELERATED CORROSION RATE.” Various numbers of categoriescan be used to classify the severity and various range values can beused for each category.

In some embodiments, the monitoring and conversion circuit 110 does notinclude corrosion rate circuit 134 and the corrosion level and corrosionrate calculations discussed above are performed by another device suchas, e.g., monitoring platform 230. The other device, e.g., monitoringplatform 230, can be implemented using a cloud networking system andincludes a computational engine to perform the corrosion level andcorrosion rate calculations discussed above. In such cases, the measuredelectrical characteristic and/or a change in the measured electricalcharacteristic (or information related to the electrical characteristic)can be transmitted by control unit 104 to the other device forprocessing. Whether performed by monitoring and conversion circuit 110or an external device (e.g., monitoring platform 230), the informationrelated to electrical characteristic values, changes in the electricalcharacteristic values, corrosion level, and/or corrosion rate can betransmitted to a user. The user can receive an indication of theseverity of the corrosion rate in text format (e.g., NORMAL,INTERMEDIATE, ACCELERATED), as the actual value (e.g., in mpy or mmy),as a color indication (e.g., green for normal, yellow for intermediate,and red for accelerated) and/or using some other indication.

In some embodiments, the weight loss is calculated based on a change inan electrical characteristic other than continuity. For example, whenresistance of each coupon portion 106 is being monitored, the corrosionrate circuit 134 correlates the change in resistance values to a loss ofweight (e.g., in grams) per area of the respective coupon portions 106.In some embodiments, when more than one wire loop 105 is used, the lossof weight can be averaged over the number of wire loops 105. Forexample, the calculated change in resistance readings of the wire loops105 can be averaged. The corrosion rate circuit 134 can correlate theloss of weight per area of the coupon portion 106 to an estimated lossof weight per area of the equipment being monitored, e.g., the loss ofweight per area of the wall of pipe 150. The correlations cam bedetermined empirically (e.g., the correlation between change inresistance values to the estimated loss of weight per area of the couponand the correlation between the estimated loss of weight per area of thecoupon and the estimated loss of weight per area of the equipment).Similarly, a change in a voltage measurement of the coupon portion 106,a current measurement through coupon portion 106, and/or an inductancemeasurement of coupon portion 106 can be correlated to loss of weightper area of the coupon portion 106, which can then be used to calculatethe loss of weight per area of the equipment being monitored.

When more than one wire loop 106 is used, the level/rate of corrosioncalculated using the change in electrical characteristic of one couponportion 106 can be compared to the level/rate of corrosion calculatedusing the other coupon portions 106, as a means to verify the accuracyof the level of corrosion and/or the rate of corrosion. For example, thecontinuity of the thinnest coupon portion 106 is compared to thecontinuity results of the other coupon portions for inconsistencies. Asan example, if the open circuit pattern deviates from the thinnestcoupon opening first to the thickest coupon opening last, an alert canbe initiated indicating that the corrosion readings may be unreliable.That is, if a coupon portion 106 indicates that it is open but a thinnercoupon portion 106 still indicates continuity, the monitoring andconversion circuit 110 (or another device) can be configured to initiatean alert that the readings from sensor assembly 102 are unreliable. Themonitoring device 100 can not use electrical characteristic readings(e.g., voltage, current, resistance, inductance, etc.) that are badand/or are suspect when calculating the change in the electricalcharacteristic for the coupon portions 106. For example, if thelevel/rate of corrosion calculated from monitoring coupon portion 106 ais different from the level/rate of corrosion calculated from monitoringcoupon portions 106 b-106 d by a predetermined amount, the monitoringdevice 100 can be configured to ignore (e.g., not use) the electricalcharacteristic readings from coupon portion 106 a and keep monitoringthe other coupon portions, e.g., coupon portions 106 b-106 d in thiscase. The corrosion level and/or the corrosion rate can be determined inreal time based on the current and historical electrical characteristicreadings.

As depicted in FIG. 6, the monitoring device 100 can include atemperature sensor 120. The temperature sensor 120 can be disposed insensor assembly 102 and senses the temperature of the corrosiveenvironment. For example, the temperature sensor 120 can sense thetemperature of the inside of pipe 150. The monitoring and conversioncircuit 110 can include a temperature detector circuit 136 a thatreceives the signal from temperature sensor 120 and converts the sensorsignal to a temperature value. The temperature sensor 120 can be, e.g.,a thermocouple, RTD, a thermistor (NTC or PTC), or some other type oftemperature sensing device. In some embodiments, the temperature sensor120 is a 10K NTC thermistor. The temperature value from sensor 120 canbe read by appropriate circuitry in monitoring and conversion circuit110 or another device (e.g., monitoring platform 230) to predictpotential problems due to the temperature, e.g., problems such aswhether and when any water in the equipment (e.g., pipe 150) willfreeze.

In some embodiments, a second temperature sensor 125 senses the ambienttemperature outside the equipment being monitored for corrosion. Forexample, the temperature sensor 125 can sense the temperature of theambient air surrounding the pipe 150. The temperature sensor 125 can bedisposed in control unit 104, such as in the monitoring and conversioncircuit 110. The temperature sensor 125 can be disposed outside themonitoring device 100. The temperature detector circuit 136 b receivesthe signal from temperature sensor 125 and converts the sensor signal toa temperature value. In some embodiments, similar to the temperaturesensor 120, the second temperature sensor 125 is also disposed in themonitoring device 100 but is arranged such that, while the temperaturesensor 120 senses the temperature of the corrosive environment, e.g.,inside the pipe 150, the second temperature sensor 125 senses theambient temperature, e.g. outside the pipe 150. The temperature sensor125 can be, e.g., a thermocouple, RTD, a thermistor (NTC or PTC), orsome other type of temperature sensing device. In some embodiments, thetemperature sensor 125 is a 10K NTC thermistor. By sensing both thetemperature of the environment of the equipment being monitored and theambient temperature (e.g., the temperature inside and outside the pipe150), the two temperatures can be read and compared by appropriatecircuitry in monitoring and conversion circuit 110 or another device(e.g., monitoring platform 230) to predict potential problems in theequipment due to the temperature, e.g., whether and when any water willfreeze. For example, the monitoring and conversion circuit 110 oranother device (e.g., monitoring platform 230) can predict whether therewill be a failure of pipe 150 based on the temperature readings insideand/or outside the pipe 150. For example, as depicted in the flowdiagram 300 in FIG. 8, in step 310, the temperature monitoring circuit140 determines if the received equipment temperature (T_(E)) (e.g.,temperature inside pipe 150) measured by temperature sensor 120 is belowa predetermined temperature value T₁. If yes at step 310, thetemperature monitoring circuit 140 determines if the received ambienttemperature (T_(A)) from temperature sensor 125 is at or below T_(E) atstep 320. If yes at step 320, a freeze alert is issued by thetemperature monitoring circuit 140 at step 330. The freeze alert caninclude a timestamp and the value of temperatures T_(E) and T_(A). Thepredetermined temperature value T₁ can be in a range from 30 deg. F. to40 deg. F. The predetermined temperature value T₁ can depend on factorssuch as, e.g., the freezing point of the liquid in the equipment and thealtitude of the equipment. A temperature value selected from near thelower range (e.g., at or below freezing such as 30 deg. F.) will providea more reliable freeze alert but the time period to take action beforethe equipment freezes can be very short. A temperature value selectedfrom near the upper range (e.g., well above freezing such as 40 deg. F.)will provide more time to take action but the freeze alert may not be asreliable as a lower value for T₁. If no at step 320, no action is takenby the temperature monitoring circuit 140.

If no at step 310, e.g., T_(E) is above the predetermined temperaturevalue, the temperature monitoring circuit 140 determines if the receivedtemperature T_(A) is at or below the freezing point for the liquid inthe equipment being monitored, e.g., 32 deg. F., at step 340. If yes atstep 340, a freeze alert is issued by the temperature monitoring circuit140 at step 330. The freeze alert can include a timestamp and the valueof temperatures T_(E) and T_(A). If no a step 340, no action is taken bythe temperature monitoring circuit 140. When issued, the freeze alerts,timestamps, information related to the temperatures T_(E) and T_(A),including the temperature values and potential problems, can betransmitted to a remote user, e.g., a user using mobile device 210and/or stationary electronic device 215. In some embodiments, theperformance of the steps in flow diagram 300 can be done in anotherdevice (e.g., monitoring platform 230) or shared between the monitoringand conversion circuit 110 and another device (e.g., monitoring platform230). For example, one or more steps 310 to 340 can be performed by themonitoring and conversion circuit 110 and any remaining steps can beperformed by the other device (e.g., monitoring platform 230). Forexample, monitoring platform 230 can perform the step 330 and issue thefreeze alert to the user. The temperature monitoring circuit 140 cancollect temperature data for the equipment temperature (T_(E)) measuredby temperature sensor 120 and the ambient temperature (T_(A)) fromtemperature sensor 125 and the other device, e.g., monitoring platform230, resides on a cloud networking system and includes a computationalengine to perform the freeze alert calculations and transmittals to theuser.

In some embodiments, the monitoring device 100 includes a waterdetection circuit 138 to sense the presence or absence of water in theequipment being monitored, e.g., in pipe 150. The water detectioncircuit 138 can use information derived from two of the coupon portions106 a-106 d to detect the water. For example, the monitoring and waterdetection circuit 138 can sense a conductance between any two couponportions 106 to determine whether there is water present between thecoupon portions 106 a-106 d. When there are more than two couponportions 106 in sensor assembly 102, voltage can be used to sensewhether there is conductance between the two thickest coupon portions106. For example, a voltage signal can be provided to one end of thesecond thickest coupon portion 106 and one end of the thickest couponportion 106 is checked for the voltage signal. A voltage signal willexist if the sensor assembly 102 is in water. In this way, if thethinnest coupon portions 106 corrode away, the two thickest couponportions 106 will still be able to detect for water. In someembodiments, the water detection circuit 138 includes a voltage dividercircuit that includes a reference resistor having a predeterminedresistance and the other “resistor” of the voltage divider circuit isthe resistance of the current flow path between the two thickest couponsand the air and/or medium between them. For example, as depicted in FIG.7, relay circuit 130 can include a voltage divider circuit 164 that canbe used for determining the presence of water. The voltage dividercircuit 164 includes relay K5, a voltage source providing voltageV_(IN), and a reference resistor R_(REF2) having a known resistance.Reference resistor R_(REF2) also serves as a pull-down resistor to keepthe voltage V_(W) from floating when the respective coupon portion 106has corroded open and/or when relay K5 is de-energized. The relay K5 canbe operated, e.g., by a microprocessor (not shown) or other circuit,which can be part of the monitoring and conversion circuit 110. Themicroprocessor or other circuit can be part of the relay circuit 130. Atleast two of the coupon portions 106 can be connected to the voltagedivider circuit in relay circuit 130 when K5 is operated. In theembodiment depicted in FIG. 7, coupon portions 106 c and 106 d, whichcan be the second thickest and thickest coupon portions, respectively,can be used for the detection of water. For example, when relay K5 isenergized, a voltage V_(IN) can be applied to one end of coupon portion106 c via terminal K5-3 of relay contact K5A. A voltage V_(W) can beread at one end of the coupon 106 d via terminal K5-9 of contact KSB.The voltage V_(W), which corresponds to a resistance between the twocoupons, can be transmitted to and measured by water detection circuit138. The water detection circuit 138 and/or an external device (e.g.,monitoring platform 230) reads and compares the voltage V_(W) readingsto a predetermined value that corresponds to a presence or absence ofwater in the sensor assembly 102, e.g., between coupon portions 106 cand 106 d. Where the monitoring device 100 is installed in a pipingsystem, the presence of water in a “dry-pipe” system or the absence ofwater in a “wet-pipe” system can be an indication of a problem in thepiping system. An alert can be sent to a user when there is anindication that a problem exists in the piping system. The alert can besent with a timestamp. The same monitoring device 100 can be used forboth “wet-pipe” and “dry-pipe” systems. The orientation of the sensorassembly 102 in the piping system can be based on the type of system.For example, as depicted in FIG. 9A, for “dry-pipe” system, the sensorassembly 102 can be located at the bottom half of the pipe, such as nearthe bottom. For example, the sensor assembly 102 can be disposed at anangle a in a range of ±60 degrees, such as ±45 degrees, and in someembodiments ±30 degrees, with zero degrees being the bottom of the pipe.For a dry-pipe system, the sensor assembly 2 can be mounted at anexpected water-air boundary level that represents a water level at whicha corrective action needs to be taken. For example, a small level ofwater in a dry-pipe system may not be a concern, but at some point thewater level may reach a point where corrective action needs to be taken,e.g., checking for leaks in valves. For a “wet-pipe” system, as depictedin FIG. 9B, the sensor assembly 102 can be located at the top half ofthe pipe, such as near the top. For example, the sensor assembly 102 canbe disposed at an angle θ in a range of ±60 degrees, such as ±45degrees, and in some embodiments ±30 degrees, with zero degrees beingthe top of the pipe. The sensor assembly 2 can be mounted at an expectedwater-air boundary for the wet-pipe system and, in some embodiments,mounted sensing the water side of the water-air boundary. The sensorassembly 2 can be mounted onto a mechanical tee, an elbow tee, anendcap, or some other mounting assembly. The mounting can be adjustableso that the sensor assembly 2 can be moved relative to the pipe. Forexample, the sensor assembly 2 can be mounted onto a grooved mechanicaltee or a grooved endcap so that the positon of the sensor assembly 2 canbe adjusted relative to the pipe 150. An adjustable mounting allows formodifications to the mounting angle if system conditions change and/orthe initial mounting angle was not correct, e.g., not correct withrespect to the location of the water-air boundary.

If there are less than two coupon portions 106 that are good, thepresence of water detection can be stopped until the sensor assembly 102is replaced. However, if a coupon portion 106 has opened up, it canstill be used for detecting the presence of water depending on how muchof an open coupon portion 106 still exists. In this case a second coupon106 is not needed to sense for water. For example, the water detectioncircuit 138 can use the open coupon portion to sense the conductance bytransmitting a voltage signal at one end of the open coupon and checkingfor the voltage signal at the other end. A freeze alarm may be initiatedonly if water is detected and the temperature monitoring circuit 140indicates that there is a chance the detected water can freeze. In thisway, the freeze alarm can be not initiated when water is not detected toreduce nuisance alarms.

As depicted in FIG. 6, the monitoring device 100 can include atransmission circuit 116 that includes a transmitter or transceiver fortransmitting sensor values and/or information derived from the sensorvalues such as, for example, continuity readings, voltage readings,current readings, temperature readings (ambient and/or equipmentenvironment), water freeze indications, inductance values, presence ofwater indication, resistance values, change in the resistance values,corrosion level values, corrosion rate values, timestamp values, and/orother sensor values and/or information to external devices (e.g.,monitoring platform 230—see FIG. 10) via, e.g., communication network220 (see FIG. 10). In addition to the various values and informationdiscussed above, the transmission circuit 116 can also transmit otherinformation generated by the monitoring device 100 such as the status ofthe monitoring device 100 (e.g., on-line, off-line, working properly,not working, needs repair, and/or some other status value), status ofthe individual voltage, current, inductance, and/or temperature sensors(e.g., working, not working, value out of range, and/or some otherinformation concerning the sensors), status of the wire loops (e.g.,closed or open (broken) loop, expected life, or some other informationconcerning the wire loops), and/or some other information related to thereadiness of monitoring device 100.

The transmission circuit 116 can use wired and/or wireless networks tocommunicate the values and/or information to the external devices. Thetransmission circuit 116 can use a wireless network to communicate thevalues and/or information to the external devices. The wireless networkcan have a range of up to 3 miles. In some embodiments, the transmissioncircuit 116 can transmit the values and/or information to a gateway(discussed further below) using the wireless network, and the gatewaytransmits the values and/or information using a cellular or IP-basednetwork to the external devices via communications network 220. Thetransmission circuit 116 can use a LoRaWAN wireless network via aMultiConnect® xDot™ made by MultiTech. In some embodiments, thetransmission circuit 116 can be configured to transmit the values and/orinformation over a period of time in batches.

The control unit 104 can include a power source 112. The power source112 provides power to the monitoring and conversion circuit 110. Thepower source 112 can be a battery, such as a battery that is“off-the-shelf.” In some embodiments, the battery can be a lithium ionbattery (or batteries), which provides a long battery life. The batterycan last 6 to 10 years without the need for replacement. The powersource 112 can be monitored by a power monitoring circuit 112 a thatprovides an alert or alarm if there is a problem with the power source112. For example, if the power source 112 is a battery, the power sourcemonitoring circuit 112 a can provide an alert/alarm when the battery islow and/or needs to be replaced. In some embodiments, the battery is arechargeable battery while in other embodiments the battery is replacedafter it is discharged. In case of a rechargeable battery, the power tocharge the battery in power source 112 can be supplied by a DC or AC busconnected to a utility grid and/or supplied by solar cells. In someembodiments, the battery of power source 112 is not field replaceable orrechargeable. In this case, the battery can be configured to last theexpected life of the pipe 150 and/or the monitoring device 100 can beshipped to a service center for battery replacement. In someembodiments, the power source 112 converts power from an external sourcesuch as, for example, the DC or AC power bus, which can be connected toa plurality of monitoring devices 100.

In some embodiments, the monitoring and conversion circuit 110 caninclude local memory (e.g., machine-readable medium) to record and storeone or more of reference values (e.g., V_(IN), V_(REF1), V_(REF2)), themeasured sensor values and/or electrical characteristic values (e.g.,V_(C), V_(W), other voltage values, current values, inductance values,continuity values, and/or temperature values), the calculated electricalcharacteristic values (e.g., resistance), the calculated chance inelectrical characteristic values, the calculated corrosion level/ratevalues, and/or other calculated and/or determined information. Themonitoring and conversion circuit 110 can include look-up-tables,databases, equations, or some other data conversion method that includesinformation related to the correlations, as discussed above, between oneor more of the following: resistance values, change in resistancevalues, coupon weight loss per area values, equipment weight loss perarea values, and/or corrosion level/rate values. The monitoring andconversion circuit 110 can include look-up-tables, databases, equations,or some other data conversion method to make the correlation between thevoltage values and the presence or absence of water determination, andto make the correlation between temperature values and the determinationof potential problems for the equipment, e.g., a determination as towhether and when the water will freeze. An external device (e.g.,monitoring platform 230—see FIG. 10) can include look-up-tables,databases, equations, or some other data conversion method to make thecorrelations as discussed above. The external device can also includememory (e.g., machine-readable medium) to record and store one or moreof reference values (e.g., V_(IN), V_(REF1), V_(REF2)), the measuredsensor values and/or electrical characteristic values (e.g., V_(C),V_(W), other voltage values, current values, inductance values,continuity values, and/or temperature values), the calculated electricalcharacteristic values (e.g., resistance), the calculated chance inelectrical characteristic values, the calculated corrosion level/ratevalues, and/or other calculated and/or determined information.

The corrosion monitoring, temperature monitoring, water detectionmonitoring and/or transmitting functions discussed above can beincorporated in to a one or more programmable microprocessors. Forexample, as depicted in FIG. 6, a microprocessor 145 can be programmedto perform the functions of the corrosion detector circuit 132, thecorrosion rate circuit 134, the temperature monitor circuit 140, thewater detector circuit 138, and/or the transmitter circuit 116. Theprogrammable microprocessor can be an Advanced RISC Machines (ARM)processor such as, e.g, a MultiConnect® xDot™ that communicates over aLoRaWAN network. The programmable processor 145 can receive thetemperature feedback signals from temperature detector 120 and/ortemperature detector 125. The programmable processor 145 can thenperform the functions of temperature monitoring circuit 140 (e.g.,determining freeze alerts) as discussed above. In some embodiments, therelays K1-K4 are connected to and operated by the programmable processor145, and the programmable processor 145 is configured to read thevoltage signals from the corresponding relay contacts as discussedabove. The programmable processor 145 can then perform the functions ofthe corrosion detector circuit 132 and/or the corrosion rate circuit 134as discussed above. The programmable processor 145 can be connected torelay K5 and be configured to read the voltage signals from the relaycontact. The programmable processor 145 can then perform the functionsof the water detector circuit 138 as discussed above.

In some embodiments, the monitoring device 100 can continuously measurethe coupon voltage values and the temperature values and/or continuouslytransmit the measured values. Depending on the type of system and theenvironment that the equipment is installed in, corrosion of theequipment to any significant degree may not be detected for years. Inaddition, even when the corrosion is detected, the progression of thecorrosion may occur over months or years. In such cases, a constantdrain on the power source 112 by continuously sending current throughthe wire loops 105 can be undesirable and considered a waste of energyand/or inefficient. Similarly, continuously checking the temperature orthe presence of water may not be worth the cost to battery life. Forexample, if the temperatures are above freezing and/or fairly constant,a once a day check may be sufficient to protect the equipment.Accordingly, in some embodiments, the microprocessor 145 or one or moreof the individual circuits in the monitoring and conversion circuit 110(e.g., the corrosion detector circuit 132, the corrosion rate circuit134, the temperature monitoring circuit 140, and/or the water detectorcircuit 138 is programmed to only take readings for a predeterminedduration of time. The predetermined duration of time can range from afew seconds to a few minutes depending on the number of measurementsthat are required. For example, each corrosion related, temperaturerelated, and/or water detection related measurement can be taken apredetermined number of times. When more than one measurement is taken,the measurements can be averaged. In addition to limiting the durationof time that the readings are taken, the time period between when themicroprocessor 145 or the appropriate circuit takes the corrosionrelated, temperature related, and/or water detection related measurementcan be based on a predetermined time period (e.g., every predeterminednumber of minutes, days, weeks, months, and/or years). The predeterminedtime periods for the respective measurements can be set independently.For example, the corrosion related and water detection measurements canbe performed once a day while the temperature related measurements canbe performed every minute. The time period between when the measurementsare taken can be based on one or more of the following performancecriteria: required battery life, remaining battery life, the level ofcorrosion, the rate of corrosion, the temperature of the equipmentenvironment, the ambient temperature, the presence or absence of water,and/or some other performance criteria. For example, if the monitoringdevice 100 is required to be installed for a period of, e.g., 10 years,the microprocessor 145 or the appropriate circuit can be configured totake into account this factor when determining when and/or how often totake the measurements. The microprocessor 145 or the appropriate circuitcan be configured to take the battery life (e.g., high/low, number ofyears remaining) as another factor to take into consideration. The rateof corrosion and the level of corrosion are also factors that can beused to determine when and/or how often to take the measurements. Forexample, at initial installation, when the rate of corrosion and/or thelevel of corrosion is expected to be low, the microprocessor 145 orcircuit 132 and/or 134 can be configured such that the time periodbetween when corrosion related measurements are relatively longinitially and then gradually or periodically shortened as the rateand/or level of corrosion increases. In situations where the corrosionrate or level is not a primary concern but the temperature is a primaryconcern due to, e.g., water freezing concerns, the microprocessor 145 orcircuit 140 can use the equipment environment temperature fromtemperature sensor 120 and/or ambient temperature from temperaturesensor 125 as factors in determining how often to power up the circuits.In some embodiments, to prevent electrical interactions, e.g.,unintended current flow, that can accelerate or decelerate the corrosionof the coupon portions 106, the relay circuit 130 breaks the connection,e.g., by opening the contacts on the relays K1-K5, between the wireloops 105 and the relevant circuits in monitoring and conversion circuit110.

Operation of the transmission circuit 116 can be regulated in order toconserve power. In some embodiments, the values and/or informationtransmitted to and measured by the microprocessor 145 (or individuallyfrom the corrosion detector circuit 132, the corrosion rate circuit 134,the temperature monitor circuit 140, and/or the water detector circuit138) can be transmitted by the transmitter 116 as respectivemeasurements are being made. In some embodiments, the time period fortransmission of the measured values and/or information is independent ofthe time period that the measurements are made. For example, thetransmission circuit 116 can transmit values and/or status informationonce each day or some other predetermined time period regardless of whenor how often the measurements are made. The measured values and/orstatus information can be transmitted responsive to detecting a changein the measured values. In some embodiments, the measured values and/orstatus information are transmitted only when the value changes by apredetermined amount or the status information changes. For example, thetemperature readings from temperature sensors 120 and 125 can betransmitted by transmitter circuit 116 when they change by apredetermined amount such as, e.g., 2 deg. F. Similarly, the continuitystatus (open/closed) of a coupon portion 106 and/or the water presencestatus can be transmitted responsive to detecting that the respectivestatus has changed (a coupon has open circuited (broken) or has opencircuited out of sequence (i.e., a larger coupon has broken before asmaller coupon in which case an error status is transmitted), or thewater presence status shows a change from “wet” to “dry” or a changefrom “dry” to “wet”).

FIG. 10 depicts an example of operating environment 200, which mayinclude one or more mobile devices 210 (e.g., a mobile phone, tabletcomputer, mobile media device, mobile gaming device, vehicle-basedcomputer, wearable computing device, portable computer, or otherportable communication device), stationary electronic device 215 (e.g.,desktop computers, servers, mainframes, or another type of non-portableelectronic device), communications network 220, monitoring platform 230(e.g., running on one or more remote servers or mainframes), monitoringsystem 270 (including one or more monitoring devices 100, localprocessing unit 235, and/or gateway unit 400) located in a building 240,user management interface 250, and a customer database 260. In someembodiments, the end user can monitor, e.g., by means of an app on themobile device 210 and/or the stationary electronic device 215, the levelof corrosion, the rate of corrosion, the thickness of the equipment(e.g., thickness of the pipe walls), the temperature of the equipmentenvironment (e.g., temperature inside the pipe), the ambient temperature(e.g., temperature outside the pipe), and/or the presence or absence ofwater by means of an app on the mobile device 210 and/or electronicdevice 215. Information such as sensor values, the status of themonitoring system 270 (e.g., on-line, off-line, working properly, notworking, needs repair, and/or some other status value), status of theindividual voltage, current, inductance, continuity, and/or temperaturesensors (e.g., working, not working, value out of range, and/or someother information concerning the sensors), status of the corrosionsensors (e.g., closed or open (broken), expected life, or some otherinformation concerning the corrosion sensors), and/or some otherinformation related to the readiness of corrosion monitoring system 270can be transmitted to the mobile device 210 and/or electronic device215. The mobile device 210 and/or electronic device 215 can providealerts, predicted maintenance times, predicted failures, or otherinformation that shows the status of the equipment being monitored,e.g., a piping system, and/or the monitoring system 270.

Mobile devices 210, stationary electronic device 215 and the monitoringsystem 270 can include network communication components that enablecommunication with remote hosting servers or mainframes (e.g.,monitoring platform 230), other stationary computers and servers, orother portable electronic devices by transmitting and receiving wirelesssignals using licensed, semi-licensed or unlicensed spectrum overcommunications network 220. In some embodiments, communications network220 may comprise multiple networks, even multiple heterogeneousnetworks, such as one or more border networks, voice networks, broadbandnetworks, service provider networks, Internet Service Provider (ISP)networks, and/or Public Switched Telephone Networks (PSTNs),interconnected via gateways operable to facilitate communicationsbetween and among the various networks. Communications network 220 canalso include third-party communications networks such as a LoRaWANnetwork, a Global System for Mobile (GSM) mobile communications network,a code/time division multiple access (CDMA/TDMA) mobile communicationsnetwork, a 3rd or 4th generation (3G/4G) mobile communications network(e.g., General Packet Radio Service (GPRS/EGPRS)), Enhanced Data ratesfor GSM Evolution (EDGE), Universal Mobile Telecommunications System(UMTS), or Long Term Evolution (LTE) network), or other communicationsnetwork. In some embodiments, communication network is a cloud-basednetwork, such as a cloud-based backend server that includes thecomputational engines to calculate the corrosion, freeze alert, and/orwater presence calculations discussed above.

Various components (not shown) may be included in mobile devices 210 toenable network communication. For example, a mobile device 210 may beconfigured to communicate over a GSM mobile telecommunications network.As a result, the mobile device 210 or components of the corrosionmonitoring system 270 may include a Subscriber Identity Module (SIM)card that stores an International Mobile Subscriber Identity (IMSI)number that is used to identify the mobile device 210 on the GSM mobilecommunications network or other networks, for example, those employing3G and/or 4G wireless protocols. If the mobile device 210, stationaryelectronic device 215 or monitoring system 270 is configured tocommunicate over another communications network, the mobile device 210,stationary electronic device 215 or components of the monitoring system270 may include other components that enable it to be identified on theother communications networks.

In some embodiments, mobile devices 210, stationary electronic device215 or components of the monitoring system 270 in building 240 mayinclude components that enable them to connect to a communicationsnetwork using Generic Access Network (GAN) or Unlicensed Mobile Access(UMA) standards and protocols. For example, a mobile device 210 and/orelectronic device 215 may include components that support InternetProtocol (IP)-based communication over a Wireless Local Area Network(WLAN) and components that enable communication with thetelecommunications network over the IP-based WLAN. Mobile devices 210,stationary electronic device 215 or components of the monitoring system270 may include one or more mobile applications that need to transferdata or check-in with monitoring platform 230.

In some embodiments, monitoring platform 230 receives signals regardingthe state of one or more monitoring systems 270. The signals canindicate the current status of a variety of system components. Forexample, the signals can include information related to the level ofcorrosion, the rate of corrosion, the thickness of the equipment (e.g.,thickness of the pipe walls), the temperature of the equipmentenvironment (e.g., temperature inside the pipe), the ambient temperature(e.g., temperature outside the pipe), and/or the presence or absence ofwater. Monitoring platform 230 can receive signals related to otherinformation such as sensor values, the status of the monitoring system270 (e.g., on-line, off-line, working properly, not working, needsrepair, and/or some other status value), status of the individualvoltage, current, inductance, continuity, and/or temperature sensors(e.g., working, not working, value out of range, and/or some otherinformation concerning the sensors), status of the corrosion sensors(e.g., closed or open (broken) loop, expected life, or some otherinformation concerning the corrosion sensors), and/or some otherinformation related to the readiness of monitoring system 270. Themonitoring platform 230 can provide alerts, predicted maintenance times,predicted failures, or other information that shows the status of theequipment being monitored, e.g., a piping system, and/or the monitoringsystem 270 in the building 240 to external devices such as, e.g., mobiledevice 210 and/or stationary electronic device 215. In some embodiments,the monitoring platform 230 is a cloud-based backend server thatincludes the computational engines to calculate the corrosion, freezealert, and/or water presence calculations discussed above.

Monitoring platform 230 can provide a centralized reporting platform forcompanies having multiple properties with monitoring systems 270. Forexample, a hotel chain or restaurant chain may desire to monitor pipingsystems in multiple properties via monitoring platform 230. Thisinformation can be stored in a database in one or more monitoring systemprofiles. Each of the monitoring system profiles can include a locationof a monitoring system 270, a monitoring system identifier, a list ofcomponents of the monitoring system 270, a list of sensors available onthe monitoring system 270, current and historical state information(including information related to the sensors, the level/rate ofcorrosion, the temperature of the water, presence or absence of water,and/or status of the monitoring system 270, etc.), contact information(e.g., phone numbers, mailing addresses, etc.), maintenance logs, andother information. By recording the maintenance logs, for example,monitoring platform 230 can create certifiable maintenance records tothird parties (e.g., insurance companies, fire marshals, etc.) which canbe stored in customer database 260.

The monitoring system 270 in building 240 can include a local processingunit 235 that communicates with one or more monitoring devices 100.Local processing unit 235 can be configured to receive the sensor valuesand/or other information, as discussed above, from one or more of themonitoring device 100 and transmit the sensor values and/or otherinformation to monitoring platform 230 via, e.g., communications network220. In some embodiments, local processing unit 235 can directlycommunicate the sensor values and/or other information from one or moremonitoring devices 100 to monitoring platform 230. The monitoring system270 in building 240 can include a gateway 400 that can communicate withone or more local processing units 235 and the local processing unit 235can transmit the sensor values and/or other information from one or moremonitoring devices 100 to the gateway unit 400. The monitoring system270 in building 240 may not include a local processing unit 235, butincludes a gateway 400 that can directly receive the sensor valuesand/or other information from the one or more monitoring devices 100 viathe transmission circuit 116, e.g., via a LoRaWAN wireless network. Thegateway unit 400, upon receiving the signal values, can then transmit(e.g., using a cellular or IP-based network) the sensor values and/orother information from one or more monitoring devices 100 to themonitoring platform 230 (or other device) via communications network220. The monitoring platform 230 (or other device) can be a cloud-basedserver or device.

In some embodiments, the monitoring devices 100 can include local memoryto record information over a period of time. Local processing unit 235can transmit the information in batches to the monitoring platform 230.These transmissions may be prescheduled (e.g., every ten minutes, everyhour, once a day, etc.), event triggered, and/or coordinate withrespective monitoring devices 100. As an example, the system may sendmore frequent transmissions based on the type of piping system (wet ordry), based on the temperature of the equipment environment, theenvironment outside the pipe, the presence or absence of water, thecorrosion level value, the corrosion rate value, and/or some othercriteria. The information recorded by the monitoring device 100 can be,e.g., information related to the sensor values (e.g., voltage, current,temperature, inductance, continuity, or some other sensor value),information related to the level of corrosion, the rate of corrosion,the thickness of the equipment (e.g., thickness of the pipe walls), thetemperature of the equipment environment (e.g., temperature inside thepipe), the ambient temperature (e.g., temperature outside the pipe),and/or the presence or absence of water, and/or information related tothe status of the monitoring system 100, including status of sensors,(e.g., closed or open (broken) coupons, on-line, off-line, workingproperly, not working, needs repair, and/or some other status value).

FIG. 11 depicts a local processing unit 235 associated with one or moremonitoring devices 100 and a gateway unit 400 capable of receivingtransmissions from one or more local processing units 235. Localprocessing unit 235 and gateway unit 400 can be low-power,microprocessor-based devices focused solely on a particular application.These units may include processing units, memories, I/O capabilities,audible and visual signaling devices, and external communicationscapabilities. For example, local processing unit 235 can includecommunications module 402, RAM 404, microprocessor 406, power source408, USB 410, Bluetooth 412, I/O's 414A-414D, piezo 416 for providing alocal audible alarm, reset 418 for resetting the alarm, and LEDs 420.Local processing unit 235 can communicate (e.g., wirelessly) with one ormore monitoring devices 100 and other devices monitoring the pipingsystem in building 240. The local processing unit 235 can directlyreceive the sensor values and/or other information from the one or moremonitoring devices 100 via the transmission circuit 116, e.g., via aLoRaWAN wireless network. Gateway unit 400 can include Wi-Fi or cellularcircuitry 422, SD card 424, RAM 426, microprocessor 428, power source430, Ethernet 432, USB 434, Bluetooth 436, I/O's 438A-438B,communications module 440, piezo 442 for providing a local audiblealarm, reset 444 for resetting the alarm, and/or LEDs 446. When gatewayunit 400 includes cellular circuitry, in some embodiments, a SIM cardthat stores an IMSI number is used to identify the gateway unit 400 on aGSM mobile communications network or other networks, for example, thoseemploying 3G and/or 4G wireless protocols.

Microprocessors 406 and 428 can have unique identifiers (IDs) programmedor set at the manufacturing level. The unique IDs can be used to link orassociate local processing unit 235 and/or gateway unit 400 withcustomers, particular monitoring systems 270, physical sites, and/orother information. Owners and system service providers can be notified,e.g., via mobile device 210 and/or stationary electronic device 215, ofthe level of corrosion, the rate of corrosion, the thickness of theequipment (e.g., thickness of the pipe walls), the temperature of theequipment environment (e.g., temperature inside the pipe), the ambienttemperature (e.g., temperature outside the pipe), the presence orabsence of water, sensor values, the status of the monitoring system270, the status of a monitoring device 100, (e.g., on-line, off-line,working properly, not working, needs repair, and/or some other statusvalue), status of the individual voltage, current, inductance,continuity, and/or temperature sensors (e.g., working, not working,value out of range, and/or some other information concerning thesensors), status of the corrosion sensors (e.g., closed or open (broken)loop, expected life, or some other information concerning the corrosionsensors), and/or some other information related to the readiness ofcorrosion monitoring system 270. Owners and system service providers canbe notified, e.g., via mobile device 210 and/or stationary electronicdevice 215, of alerts, predicted maintenance times, predicted failures,or other information that shows the status of the equipment beingmonitored, e.g., a piping system, and/or the monitoring system 270. Userprofiles enable the end user to define his or her type or types ofnotification and when they occur (any time versus specific times).Accordingly, the notification capabilities are not solely limited toalarm or alert notifications. Since the system is capable of identifyingmaintenance activity and/or normal states, the system can be configuredto notify end users, technicians and customers of the states.

I/Os 414A-414D can be simple contact closure with a mechanical option toconnect a switch to the normally open or normally closed terminals. Thiscan help accommodate a variety of system configurations and may resultin less field programming. Audible and visual warnings can be local(within the vicinity of the monitored system). For example, visualindicators may be board-based LED's 420, and audible would be a buzzeror piezo 416. Dry or wet contacts may be used to provide binary alarm,warning, supervisory, trouble or other alerts to secondary fire,security, building automation or like systems on site.

Local processing unit 235 and/or gateway unit 400 can have a variety ofexternal communications. In some embodiments, these components cansupport serial or USB communications so that the device can beprogrammed, configured or interrogated. A local Ethernet port 432(supporting POE) may also be available in some embodiments. Additionalcommunications options may include the ability to add a daughter boardfor Wi-Fi or Cellular connectivity. The local processing unit and/orgateway 400 can be configured to communicate over a LoRaWAN wirelessnetwork. This component can allow all data and events local to thesystem to a centralized server (e.g., monitoring platform 230).

FIG. 12 depicts components 500 within a monitoring platform 230.Monitoring platform 230 can include memory 505, one or more processors510, communications module 515, status module 520, identification module525, data collection module 530, technician locator module 535, servicerequest module 540, recordation module 545, analytics engine 550,prediction engine 555, and graphical user interface (GUI) generationmodule 560. Each of these modules can be embodied as special-purposehardware (e.g., one or more ARMs, ASICS, PLDs, FPGAs, or the like), oras programmable circuitry (e.g., one or more microprocessors,microcontrollers, or the like) appropriately programmed with softwareand/or firmware, or as a combination of special-purpose hardware andprogrammable circuitry. Various combinations of such modules may beimplemented. For example, status module 520 and identification module525 can be combined into a single module for determining the status ofone or more corrosion monitoring systems 270.

Memory 505 can be any device, mechanism, or populated data structureused for storing information. In accordance with some embodiments of thepresent technology, memory 505 can encompass any type of, but is notlimited to, volatile memory, nonvolatile memory and dynamic memory. Forexample, memory 505 can be random access memory, memory storage devices,optical memory devices, media magnetic media, floppy disks, magnetictapes, hard drives, SDRAM, RDRAM, DDR RAM, erasable programmableread-only memories (EPROMs), electrically erasable programmableread-only memories (EEPROMs), compact disks, DVDs, and/or the like. Inaccordance with some embodiments, memory 505 may include one or moredisk drives, flash drives, one or more databases, one or more tables,one or more files, local cache memories, processor cache memories,relational databases, flat databases, and/or the like. In addition,those of ordinary skill in the art will appreciate many additionaldevices and techniques for storing information that can be used asmemory 505.

Memory 505 may be used to store instructions for running one or moreapplications or modules on processor(s) 510. For example, memory 505could be used in one or more embodiments to house all or some of theinstructions needed to execute the functionality of communicationsmodule 515, status module 520, identification module 525, datacollection module 530, technician locator module 535, service requestmodule 540, recordation module 545, analytics engine 550, predictionengine 555 and/or GUI generation module 560. While not shown in FIG. 12,in some embodiments, an operating system can be used to provide asoftware package that is capable of managing the hardware resources ofmonitoring platform 230. The operating system can also provide commonservices for software applications running on processor(s) 510.

Communications module 515 can be configured to manage and translate anyrequests from external devices (e.g., mobile devices 210, electronicdevice 215 corrosion monitoring systems 270, etc.) or from graphicaluser interfaces into a format needed by the destination component and/orsystem. Similarly, communications module 515 may be used to communicatebetween the system, modules, databases, or other components ofmonitoring platform 230 that use different communication protocols, dataformats, or messaging routines. For example, in some embodiments,communications module 515 can receive measurements of the current stateof one or more monitoring systems 270. Communications module 515 can beused to transmit status reports, alerts, logs, and other information tovarious devices.

Status module 520 can determine the status of the equipment beingmonitored, e.g., piping systems, corresponding to one or more corrosionmonitoring systems 270. For example, status module 520 may usecommunications module 515 to directly request a status of equipmentmonitored by a monitoring system 270 from one or more gateways 400 orlocal processing units 235. Identification module 525 can be configuredto receive sensor data and/or other information, as discussed above,generated by the monitoring system 270, e.g., sensor data andinformation generated by monitoring devices 100. Using the receivedsensor data and/or other information, identification module 525 can thenidentify an operational status of the equipment being monitored by themonitoring system 270, e.g., a piping system. The operational statusand/or the sensor data itself can then be recorded within a monitoringprofile in a database for the monitored equipment. As a result, themonitoring profile can provide a history of the operational status ofthe equipment monitored by the monitoring system 270 over time. Inaccordance with some embodiments, the operational status can include afunctional status indicating that the equipment monitored by themonitoring system 270 should operate as expected, a maintenance statusindicating when the monitored equipment should undergo maintenanceand/or inspection, and an inoperative status indicating that themonitored equipment may not operate as expected.

Data received via communications module 515 can be accessed by datacollection module 530 for processing, formatting, and storage. Datacollection module 530 can keep track of the last communication from eachof the corrosion monitoring systems 270 and generate an alert if anymonitoring device 100 fails to report on schedule (e.g., every minute,every five minutes, or other preset schedule) and/or when a request ismade. Data collection module 530 can also review the quality of the datareceived and identify any potential issues. For example, if a data setfrom a monitoring system 270 includes various sensor data, datacollection module 530 can analyze the data to determine any erraticbehavior or outliers that may indicate that a sensor is beginning tofail.

Technician locator module 535 can be configured to receive location andschedule updates from mobile devices 210 associated with technicians.Service request module 540 can be configured to identify when theoperational status of the equipment monitored by monitoring system 270,e.g., a piping system, is inoperative and identify an availabletechnician using the technician locator. As a technician is servicingthe monitored equipment, he or she may use a computer application or amobile application to report various findings, observations, partsreplaced, and the like. As this information is transmitted to monitoringplatform 230, recordation module 545 can record the information from thetechnician in the appropriate corrosion monitoring profile.

Analytics engine 550 can analyze the sensor data from one or moremonitoring devices 100 and perform the functions discussed above withrespect to corrosion rate circuit 134. The analytics engine can alsogenerate a correlation model that is predictive of when a failure of themonitored equipment is likely, e.g., due to thinning pipe walls,predictive of when freezing of the equipment, e.g., pipes, is likely tooccur, predictive of some other type of abnormal operating state of theequipment being monitored, predictive of when certain maintenance and/orinspection activities should occur, and/or predicts some other type ofabnormal operating condition and/or inspection activity. The correlationmodel (or models) can be generated based on one or more of thefollowing: sensor data relating to the electrical characteristic of eachthe corrosion sensors, e.g., coupon portions 106, the level ofcorrosion, and/or the rate of corrosion; other sensor data such as thetemperature of the equipment environment (e.g., inside the pipe) and/orambient temperature (e.g., outside the pipe), and/or the presence orabsence of water; and other types of information such as the thicknessof the equipment (e.g., the thickness of the piping wall), the equipmentmaterial, and/or observations from the technicians during inspections.Prediction engine 555 can be configured to process the sensor data inreal-time against the correlation model or models generated by theanalytics engine 550 and generate an alarm condition, an inspectionrequest based on the information gathered from the sensors in thecorrosion monitoring system 270, and/or determine the respectivemeasurement intervals for the monitoring devices 100. For example, ifthe level and/or rate of corrosion is low, the time between maintenanceinspections and/or measurement intervals can be extended. However, ifthe level and/or rate of corrosion starts to increase, the time betweeninspections and/or the measurement intervals can be decreased. Theinspection of the piping system can be based on the number of freezingand thawing cycles the piping system experienced in a given time period.Analytics engine 550 can monitor the sensor data and generate othertypes of analytics. In some embodiments, part or all of the functions ofanalytics engine 550 and/or prediction engine 555 can be incorporatedinto local processing unit 235 and/or monitoring device 100.

GUI generation module 560 can generate one or more GUI screens thatallow for interaction with a user. GUI generation module 560 cangenerate a graphical user interface allowing a user to set preferences,review reports, create profiles, set device constraints, and/orotherwise receive or convey information about device customization tothe user. For example, GUI generation module 560 can be configured toretrieve, from the database, the information from the multiple corrosionmonitoring profiles. Once the information has been retrieved, GUIgeneration module 560 can generate a graphical user interface allowing auser to see the operational status of any of the profiles of theequipment being monitored, e.g., via mobile device 210 and/or stationaryelectronic device 215. The information generated by the analytics engine550 and/or the prediction engine 555 as discussed above can be sent tothe user and/or are available to the user via the GUI screens.

FIG. 13 is flow diagram depicted a set of operations 700 for determiningwhen to transmit a notification to a monitoring platform (e.g.,monitoring platform 230) that the equipment monitored by the monitoringsystem 270, e.g. a piping system, is not fully operative and/or requiresattention. In some embodiments, the operations depicted in FIG. 13 maybe performed by various components of the monitoring system 270,including, but not limited to, one or more monitoring devices 100, oneor more local processing units 235, and/or one or more gateway units 400associated with the monitoring system 270.

As depicted in FIG. 13, monitoring operation 710 can monitor amonitoring system 270. For example, as the sensor signals and/or otherinformation, as discussed above, from, e.g., monitoring devices 100 arereceived, determination operation 720 can determine if the monitoredequipment, e.g., a piping system, and/or the associated monitoringsystem 270 is in an abnormal state. Examples of abnormal states caninclude the monitoring and conversion circuit 110 indicating abnormalsensor readings, the level and/or rate of corrosion is outsidepredetermined limits and/or predicts failure within a predetermined timeperiod, the temperature of the equipment environment and/or ambienttemperature predict abnormal freezing/thawing conditions, the presenceof water where none should be, and/or the absence of water where thereshould be water, and the like. When determination operation 720determines that the piping system/corrosion monitoring system 270 is ina normal state, determination operation 720 branches back to monitoringoperation 710. When determination operation 720 determines that thepiping system/corrosion monitoring system 270 is in an abnormal state,then determination operation 720 branches to timing operation 730 wherea timer is initiated.

The amount of time set for the timer in timing operation 730 may bestatic (e.g., thirty seconds, five minutes, etc.) or dependent on thetype of abnormal state that is detected. For example, an abnormal leveland/or rate of corrosion condition can have a timer setting that isdifferent from a timer setting for an abnormal temperature condition ora timer setting for an abnormal presence of water. In the event multipleabnormal states are detected, timing operation 730 may set the timer tothe minimum time associate with the detected abnormalities or create anew time (e.g., an average or a weighted average).

Expiration operation 740 monitors the abnormal states and the timer.Upon expiration of the timer, if the abnormal states have all returnedto normal, then expiration operation 740 branches to monitoringoperation 710. If expiration operation 740 determines that the abnormalstates have not all returned to normal, the expiration operation 740branches to state evaluation operation 750 where a determination is madeas to whether one or more states have returned to normal. When stateevaluation operation 750 determines that one or more states havereturned to normal, state evaluation operation 750 branches to timingoperation 730 where a new timer is set. When state evaluation operation750 determines that one or more states have not returned to normal, thenstate evaluation operation 750 can branch to generation operation 760where one or more notifications can be sent to a technician and/or otherparty (e.g., building operator). The notifications may be sent via oneor more communication channels. For example, lighting a display, textmessage, e-mail, automated phone call, fax, push notification, and/orthe like.

Once the notifications have been generated, then remote timing operation770 start a time for a specified period of time. The time set by remotetiming operation 770 may be static or dynamic, as described above.Remote timing operation 770 may set the timer, at least in part, basedon whether or not a response was from the technician and/or a thirdparty in response to the notifications. Clearing operation 780 candetermine whether all the states have returned to normal before thetimer expires. When clearing operation 780 determines all states havereturned to normal, then clearing operation 780 branches to monitoringoperation 710. When clearing operation 780 determines that there is atleast one remaining abnormal state, then clearing operation 780 branchesto reporting operation 790 which sends one or more notifications to amonitoring platform 230 (or other device) that the pipingsystem/corrosion monitoring system 270 is not operative or is anabnormal state.

Having now described some illustrative implementations, it is apparentthat the foregoing is illustrative and not limiting, having beenpresented by way of example. In particular, although many of theexamples presented herein involve specific combinations of method actsor system elements, those acts and those elements can be combined inother ways to accomplish the same objectives. Acts, elements andfeatures discussed in connection with one implementation are notintended to be excluded from a similar role in other implementations orimplementations.

The phraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including” “comprising” “having” “containing” “involving”“characterized by” “characterized in that” and variations thereofherein, is meant to encompass the items listed thereafter, equivalentsthereof, and additional items, as well as alternate implementationsconsisting of the items listed thereafter exclusively. In oneimplementation, the systems and methods described herein consist of one,each combination of more than one, or all of the described elements,acts, or components.

Any references to implementations or elements or acts of the systems andmethods herein referred to in the singular can also embraceimplementations including a plurality of these elements, and anyreferences in plural to any implementation or element or act herein canalso embrace implementations including only a single element. Referencesin the singular or plural form are not intended to limit the presentlydisclosed systems or methods, their components, acts, or elements tosingle or plural configurations. References to any act or element beingbased on any information, act or element can include implementationswhere the act or element is based at least in part on any information,act, or element.

Any implementation disclosed herein can be combined with any otherimplementation or embodiment, and references to “an implementation,”“some implementations,” “one implementation” or the like are notnecessarily mutually exclusive and are intended to indicate that aparticular feature, structure, or characteristic described in connectionwith the implementation can be included in at least one implementationor embodiment. Such terms as used herein are not necessarily allreferring to the same implementation. Any implementation can be combinedwith any other implementation, inclusively or exclusively, in any mannerconsistent with the aspects and implementations disclosed herein.

Where technical features in the drawings, detailed description or anyclaim are followed by reference signs, the reference signs have beenincluded to increase the intelligibility of the drawings, detaileddescription, and claims. Accordingly, neither the reference signs northeir absence have any limiting effect on the scope of any claimelements.

Systems and methods described herein may be embodied in other specificforms without departing from the characteristics thereof. Furtherrelative parallel, perpendicular, vertical or other positioning ororientation descriptions include variations within +/−10% or +/−10degrees of pure vertical, parallel or perpendicular positioning.References to “approximately,” “about” “substantially” or other terms ofdegree include variations of +/−10% from the given measurement, unit, orrange unless explicitly indicated otherwise. Coupled elements can beelectrically, mechanically, or physically coupled with one anotherdirectly or with intervening elements. Scope of the systems and methodsdescribed herein is thus indicated by the appended claims, rather thanthe foregoing description, and changes that come within the meaning andrange of equivalency of the claims are embraced therein.

The term “coupled” and variations thereof includes the joining of twomembers directly or indirectly to one another. Such joining may bestationary (e.g., permanent or fixed) or moveable (e.g., removable orreleasable). Such joining may be achieved with the two members coupleddirectly to each other, with the two members coupled with each otherusing a separate intervening member and any additional intermediatemembers coupled with one another, or with the two members coupled witheach other using an intervening member that is integrally formed as asingle unitary body with one of the two members. If “coupled” orvariations thereof are modified by an additional term (e.g., directlycoupled), the generic definition of “coupled” provided above is modifiedby the plain language meaning of the additional term (e.g., “directlycoupled” means the joining of two members without any separateintervening member), resulting in a narrower definition than the genericdefinition of “coupled” provided above. Such coupling may be mechanical,electrical, or fluidic.

References to “or” can be construed as inclusive so that any termsdescribed using “or” can indicate any of a single, more than one, andall of the described terms. For example, a reference to “at least one of‘A’ and ‘B’” can include only ‘A’, only ‘B’, as well as both ‘A’ and‘B’. Such references used in conjunction with “comprising” or other openterminology can include additional items.

Modifications of described elements and acts such as variations insizes, dimensions, structures, shapes and proportions of the variouselements, values of parameters, mounting arrangements, use of materials,colors, orientations can occur without materially departing from theteachings and advantages of the subject matter disclosed herein. Forexample, elements shown as integrally formed can be constructed ofmultiple parts or elements, the position of elements can be reversed orotherwise varied, and the nature or number of discrete elements orpositions can be altered or varied. Other substitutions, modifications,changes and omissions can also be made in the design, operatingconditions and arrangement of the disclosed elements and operationswithout departing from the scope of the present disclosure.

References herein to the positions of elements (e.g., “top,” “bottom,”“above,” “below”) are merely used to describe the orientation of variouselements in the FIGURES. It should be noted that the orientation ofvarious elements may differ according to other exemplary embodiments,and that such variations are intended to be encompassed by the presentdisclosure.

1. A corrosion monitoring device to monitor corrosion in a pipe of afire sprinkler system, comprising: a sensor assembly including at leastone sensor portion disposed in an interior of a pipe in a fire sprinklersystem for sensing corrosion of a wall of the pipe; and a detectorcircuit to: transmit an electrical signal through the at least onesensor portion; monitor an electrical characteristic of the at least onesensor portion based on the electrical signal; compare at least one ofthe monitored electrical characteristic and a change in the electricalcharacteristic of the at least one sensor portion to at least one of apredetermined value and a previously monitored electricalcharacteristic; determine a corrosion status indicative of at least oneof a corrosion level and a rate of corrosion of the pipe wall based onthe comparison; and output an indication of the corrosion status.
 2. Thedevice of claim 1, comprising: the electrical characteristic is at leastone of a continuity of the at least one sensor portion, a resistancevalue of the at least one sensor portion, a voltage value at apredetermined location of the at least one sensor portion, a voltagedrop across the at least one sensor portion, a current value through theat least one sensor portion, and an inductance value of the at least onesensor portion.
 3. The device of claim 1, comprising: a power sourceproviding a voltage having a second predetermined value; a relay circuitthat connects a first end of the at least one sensor portion to thepower source and a second end of the at least one sensor portion to thedetector circuit; and the electrical characteristic is a continuity ofthe at least one sensor portion.
 4. The device of claim 1, comprising: apower source providing a voltage having a second predetermined value;and a relay circuit that connects a first end of the at least one sensorportion to the power source and a second end of the at least one sensorportion to the detector circuit; the electrical characteristic is acontinuity of the at least one sensor portion, the continuity indicatingwhether the respective sensor portion is open circuited or not; and thedetector circuit determines the continuity of each sensor portion basedon a voltage measurement at the second end of the at least one sensorportion.
 5. The device of claim 1, comprising: each of the at least onesensor portion is a coupon portion that corrodes at a rate that can becorrelated to a rate of corrosion of the pipe wall.
 6. The device ofclaim 1, comprising: each of the at least one sensor portion is a couponportion that corrodes at a rate that can be correlated to a rate ofcorrosion of the pipe wall; the sensor assembly includes at least twosensor portions that are coupon portions, with each coupon portionhaving a surface area, and at least one surface area of the couponportions is different from the surface areas of the other couponportions.
 7. The device of claim 1, comprising: the sensor assemblyincludes at least four sensor portions that are coupon portions, witheach coupon portion having a different surface area than the othercoupon portions.
 8. The device of claim 1, comprising: each of the atleast one sensor portion is a coupon portion that corrodes at a ratethat can be correlated to a rate of corrosion of the pipe wall, ageometric shape of each coupon portion is a cylindrical shape.
 9. Thedevice of claim 1, comprising: a corrosion rate circuit to calculate atleast one of the level of corrosion and the rate of corrosion for thepipe wall based on an estimated loss of weight of the at least onesensor portion.
 10. (canceled)
 11. The device of claim 1, comprising: atemperature sensor of the sensor assembly is disposed such that thetemperature sensor senses a temperature of the interior of the pipe; anda temperature monitoring circuit, the temperature monitoring circuitreceives a signal from the temperature sensor and determines whetherwater in the pipe will freeze based on the temperature of the interiorof the pipe.
 12. The device of claim 1, comprising: a temperature sensorof the sensor assembly is disposed such that the temperature sensorsenses a temperature of the interior of the pipe; and a temperaturemonitoring circuit, the temperature monitoring circuit receives a signalfrom the temperature sensor and determines whether water in the pipewill freeze based on the temperature of the interior of the pipe,receives a signal from an ambient temperature sensor measuring anambient temperature outside of the pipe, and determines whether thewater in the pipe will freeze based on the temperature in the interiorof the pipe and the ambient temperature.
 13. The device of claim 1,comprising: a temperature sensor of the sensor assembly is disposed suchthat the temperature sensor senses a temperature of the interior of thepipe; and a temperature monitoring circuit, the temperature monitoringcircuit receives a signal from the temperature sensor and determineswhether water in the pipe will freeze based on the temperature of theinterior of the pipe, receives a signal from an ambient temperaturesensor measuring an ambient temperature outside of the pipe, determineswhether the water in the pipe will freeze based on the temperature inthe interior of the pipe and the ambient temperature, and issues afreeze alert if the temperature of the interior of the pipe is less thana third predetermined value and the ambient temperature is less than thetemperature of the interior of the pipe.
 14. The device of claim 12,comprising: a temperature sensor of the sensor assembly is disposed suchthat the temperature sensor senses a temperature of the interior of thepipe; and a temperature monitoring circuit, the temperature monitoringcircuit receives a signal from the temperature sensor and determineswhether water in the pipe will freeze based on the temperature of theinterior of the pipe, receives a signal from an ambient temperaturesensor measuring an ambient temperature outside of the pipe, and issuesa freeze alert if the ambient temperature is less than a freeze point ofthe water in the pipe.
 15. The device of claim 1, comprising: the sensorassembly includes at least two sensor portions; and the detector circuitmeasures a resistance between any two sensor portions and determines apresence or absence of water in the equipment based on the measurement.16. A method of monitoring corrosion in a pipe of a fire sprinklersystem, comprising: transmitting an electrical signal through at leastone sensor portion disposed in an interior of a pipe in a fire sprinklersystem for sensing corrosion of a wall of the pipe; monitoring anelectrical characteristic of the at least one sensor portion based onthe electrical signal; and comparing at least one of the monitoredelectrical characteristic and a change in the electrical characteristicof the at least one sensor portion to at least one of a predeterminedvalue and a previously monitored electrical characteristic of the atleast one sensor portion to determine information that relates to atleast one of a corrosion level and a rate of corrosion of the pipe wall.17-18. (canceled)
 19. The method of claim 16, comprising: determiningwhether each of the at least one sensor portion is open circuited basedon a voltage measurement on a second end of the at least one sensorportion when a first end of the at least one sensor portion is connectedto a voltage source providing a predetermined voltage, the electricalcharacteristic is a continuity of the at least one sensor portion, eachof the at least one sensor portion is a coupon portion that isconfigured to corrode at a rate that can be correlated to a rate ofcorrosion of the pipe wall.
 20. (canceled)
 21. The method of claim 16,comprising: transmitting the electrical signal through at least foursensor portions of the at least one sensor portion that are couponportions, with each coupon portion having a different surface area thanthe other coupon portions.
 22. (canceled)
 23. The method of claim 16,comprising: calculating at least one of the level of corrosion and therate of corrosion for the monitored equipment based on an estimated lossof weight of the at least one sensor portion.
 24. (canceled)
 25. Themethod of claim 16, comprising: measuring a temperature of the interiorof the pipe; and determining whether water in the pipe will freeze basedon the temperature of the interior of the pipe.
 26. The method of claim16, comprising: measuring a temperature of the interior of the pipe;measuring an ambient temperature outside of the pipe; and determiningwhether water in the pipe will freeze based on the temperature of theinterior of the pipe and the ambient temperature. 27-70. (canceled)